The next three floors just go like usual. Hundreds of high-level monsters chilling to cold status and feeding me a ton of exp. I spend some of the MP regeneration time re-reading the dungeon book, some looking through the race and class options for Maria and the rest of the time playing with summoned Elly makeshift chess using some of the craft materials as chess pieces and some marking engraved on the ground via spears as playboard.
Not pretty but serviceable.

We finally settled on a setup for Maria. The low level and lack of equipment stats are very limiting when you can't fall back on status magic.

Not quite what I originally expected but considering the restrictions and what I've perceived of Maria's personality so far, it will have to suffice.
I would prefer to also give her valkyrie, spears just have better reach than swords, the damage types seem to be identical and flight should be very useful but she insisted on swords and this was the best I found.

Considering she's dead anyway when I as her summoner die this skill has no drawback for her.

I just hope I'll never have to find out what the actual restrictions on this skill are...

As for visuals, she's become a short-haired brunette wielding a claymore wrapped in proper plate armor. Too bad none of the stuff is really functional, at least it means I have no objection to her forgoing a helm neither does it seem to hamper her movement. Can we just call it cosplay armor at this point?

After we finalized her body I offered Maria to join in on chess as well but she felt like I was cheating with Elly in my head assisting me. And since I can't afford to summon both of them at the same time she sits those sessions out and only observes us, maybe learning a bit more about the game. Summons only come with the bare minimum in knowledge afterall and chess is deemed non-essential. A pity but one we can correct later.

I even just barely manage to reach Summoner level 3 already from those three floors. Elly was very disappointed that she didn't also level up from that. I need a lot more CHA before she does.

And then... the remaining floors are just empty. Not a monster in sight.

"Wasn't that as far as I got in the previous dungeon? I think we had to turn back at floor 17 and the 17 here was the last one filled with monsters."

"I remember it like that as well", Elly is in a serious mood for once, "so it seems we really were in the same dungeon the whole time. Just half joined by a second dungeon instance? Maybe something like that. I don't know, Jared."

"Neither do I. But let's assume that it really is the same dungeon. Honestly, that would be the worst case as we'd appear directly in front of Darius again when we leave."

(My liege, could I ask you to please call Elly back? I want to take part in this discussion as well if possible.)

"Uh, I think I can help you there, guys", Dan finally speaks to us again after an eternity of silence.

"How so?"

"The exit leads to a small village. I think there is no one there to play with though. By the way, who is your lady friend, bats?"

"Just a spirit I've summoned. Felt a bit lonely since there was no one else to talk to."

I signal to Elly to return to me.

"Uh, sorry about that. I was looking for some playmates for the floors you're currently on but no one came."

"Works for me. Gets me faster out of here."

"Ohhh... but I wanted to play more with you."

"I think we've played enough. I've been here for almost a year now."

(I wouldn't have minded you gaining a few more levels in Summoner before we leave this place. If not for giving me eventually another level then at least for the additional skill at level 5.)

(Now, now, miss Elly, we'll have plenty of opportunities to remedy this deficiency.)

(I liked it more when you called me sister...)

(If you wish I'll give it a try... dear sister), that almost sounded mocking from Maria.

(Can I assume that Elly is the big sis by age and Maria is the big sis by maturity?)

(HEY!)

(I take that as a yes.)

"Well, if you have to leave...", Dan continues in a sad tone, or as sad as a dungeon can sound, "I hope you two will at least come back to play again soon."

"Without a doubt. From what I understand it is in my interest to fully clear a couple of dungeons, this one included. We'll definitely run into each other again then."

"You're a weird monster, you know that? Beating a dungeon and all that. Oh, I know! Before you leave please wait a moment for me. I think I have a farewell present for you. You know, as a reminder of your promise. You can go on until you see the blue exit portal, we'll meet up again there."

"Uh, sure. Let's do that."

I continue walking through the empty floors. Even the boss floor is empty. Can I just walk out like that? No more boss in my way? That would probably be too easy.

(Any plans for what we do once we're outside, Jared?)

(Elly has me informed about what has happened so far, milord, I'm curious as well.)

(Not really. Our 'friend' Dan said we'd leave towards a village, so not even close to where we came from. Damn glitched reality...)

Elly adds her two cents, (if I had to guess that village will be abandoned because of the ongoing flood. Unless there's also time travel involved, and then all bets are off.)

(Yeah, and even if we got a bit stronger here that is not nearly enough to fight off all of those monsters. We'll need to check out the surrounding area and hopefully find a somewhat defensible position.)

(Do you intend to fight your way back to the fortress, Jared?)

(Depends on where we end up. Ideally, yes. Even if we can hold a given position I've no intention of enduring that for half a year or more.)

(Under the assumption that we can make it to the nearest fortress and it should be the one you were before, milord, what would be the plan then?)

(I don't know, Maria, I don't know. I'd really like to continue where I left off. Find some people I can trust, gather some leads on the demon artifact and then go from there. But after the issue with Darius that won't work. He is someone I cannot beat in a fight and given our brief history neither of us can trust the other.)

(I think you should finally do what I told you a thousand times and show him that you are a 'Lost One'. I see no other way out of this.)

(Yeah, but we can worry about that once we know what is going on outside.)

(Has your opinion on taking over a 'Lord's Mansion' changed? Still against it?)

(Honestly, I'm still not too keen on taking on a leadership role. Especially when the threat of a riot over me being a vampire looms over everything.)

(I am of the opinion that milord should do it. It would only be right for a lord to have some lands to rule over.)

(Your opinion is duly noted, Maria. But it really is not as simple as that. People will find out that I'm a vampire eventually. I still need to drink blood to survive. So I can either demand some kind of regular blood tribute or try to keep it under wraps by secretly assaulting someone, but eventually, that will be found out. Either way, they'll know. And people have prejudices against vampires, and they aren't unfounded I may add.)

(I am quite aware of those facts. I still believe it would be for the better. If it helps I shall offer my blood as well.)

(If it was that easy you'd see a lot of vampires with summoner classes for self-sustain. And if my experience with monster blood is any indication it will be worth nearly nothing.)

(As I said I am willing to offer my blood, so if you want to try, please go ahead.)

(Fine, let's get this over with.)

I summon Maria, "are you really sure you're ok with this?"

"Yes, milord."

I do as requested, bite her neck and drink some of her blood. Same deal as with the fake human monsters, a very weak taste and only the slightest bit filling. Not an angle worth pursuing in the long run.

"Yeah, it is exactly as expected. Are you ok?"

"Yes, it was... a bit different than what I expected, but I am fine."

"Good, go back now and rest."

With these words I unsummon her.

(So with that theory destroyed... any other reason why it shouldn't be a big deal to take over the 'Lord's Mansion'? Or can we postpone that problem until it is too late?)

(Maybe, aren't you forgetting someone?)

(Depends, who do you have in mind, Elly?)

(Chloe. You know, your familiar. Could you really abandon her like that?)

(Who is that? Another of our sisters?)

(No, Maria, she is a normal person. Or at least was? We're still not exactly sure what the 'familiar bond' my skill forced on her did to her. She has been a bit... off since then.)

(In that case, I think that as a gentleman it is your duty to take care of her.)

Since when am I a gentleman? I am a goddamn vampire. Gentle is kinda the opposite of what happens when I go for dinner.

(Say, Maria, I've thought you'd be more restrained like you were a few floors when you first came to be. What has changed?)

(I do not know what you speak of.)

(Uh, I think I can answer that...)

(Elly, what have you done this time?)

(So I wanted to bring Maria up to speed on our general situation but that was honestly a bit too much to get across quickly. So I took a shortcut and gave my fellow 'AI' here just a  few of the relevant ones from my memory files and, uh... I think a few of my personality files got mixed up in there?)

(So you've now basically mind-wiped her?)

(I must protest, my liege. Elly has only done what she considers to be in your best interest.)

(There are limits to how far you two should take these things. Even if you two are 'just AIs' to me you're real, like real people real, and you should at least get treated with that level of respect. Did I make myself clear?)

(Yes, milord.)

(This split personality understands as well.)

Way to ruin the mood, Elly.

We move on and reach floor 1 with no opposition but instead of the expected blue exit portal. there are just more stairs to the next floor.

(Can I file a bug report on this? The entrance should always be before floor 1 and not... what floor -28? Do I have to beat 120 floors away from my spawn point or something?)

(I'm afraid we can do nothing but move on, Jared.)

(Yeah, yeah. Maria? Is everything ok with you? You're quite silent.)

(No, everything is fine, I'm just not much of a talker.)

(Right, but don't forget to actually speak up when something happens, ok?)

(Yes, I will. Don't worry about me.)

And on floor 0 there waits the promised rematch with the green wall. If I could I'd like to pass on that...

(Seems like I wasn't the only one out training.)

(I think it was level 16 before and just a regular slime, not a queen variant. Also, Disperser is new.)

(Why do I feel like it is still optimized to annoy me.)

(Well, you two were going to get one shot anyway.)

(Oh for... Do you want to be my equal and opposite, Haze? Slime for vampire, both classic RPG monsters, even the highest slash boss variant for both of us. Golem to my survivor as the defense line. Gleam to my wizard as caster. Disperser as the counterpart to my summoner...)

(...wall for your tendency to hide behind those. I think you read too much into this.)

(Maybe, but it still feels like it is mocking me. On the upside its off-screen training caused it to lose the skill that worried me the most, no more regeneration for you! I think this is the first time where a villain should have rather forgotten to level grind if they are serious about winning.)

I shoot an dark spell at it.

So much for stopping its spell casting with the curse status...

The boss casts its earth spell and I have gone out of the way long before it was even ready to fire. 

(Uh, yeah, that'll take ages to take down... like weeks, Jared.)

(Hmm... I have a dumb idea, Elly.)

(We better be ready for anything now, Maria...)

(Do you see the gap over the boss? Can you try to fly behind it and check if it can attack there?)

(I don't see the point. I doubt I can even scratch that thing's defense. And if it can attack I'm dead.)

(So what? You're now my summon. You'll be back after a one-week vacation.)

(I'd like to pass on that but you are the boss...)

I shoot another spell at the boss to get its attention away from Elly while she flies through the gap as discussed.

(What is your plan, my liege?)

(I want to get you two in attack range. It negates my best source of damage and has high magic resistance on top. But its physical defense isn't that high.)

"4̵̠̈́8̸͙̿4̶͈̂5̷̧͘5̷̢͆9̵̠͌2̷͔͠1̵̯̽2̷̦̀0̶̺̽ ̸͉́5̵̫͝3̶͎̌5̷̯͋4̸̲̑4̷̻͋f̸͓͘5̵̼̆0̴̨̍2̴̻͐0̵͓͂ ̴͈̃5̵̬̀4̶͍̊4̸̥͗8̸͕͆4̴̝́1̷̮̚5̷̏͜4̴̮͂2̶̈́ͅ1̶̭̚ ̷͈̋"

After a minute Elly screams, "I seem to be safe here! Now what?"

"Hit it!"

"I already did! That was only 47 damage!"

Oh, so I don't get system notifications for what damage my summons do, good to know.

"Okay, then come back!"

I shoot yet another spell as a distraction, it also fails to inflict the status effect. Guess the boss's resistance is too high for me. Also, shouldn't my summons draw fire away from me? This isn't working as I hoped...

Elly stands before me again, "so how did this help us?"

"Depends on how the rest goes. Do you think you can carry Maria behind the boss?"

"Uh, I think I can. The 'heavy' armor is just for show after all."

I summon Maria as well.

"So the plan is simple. Elly, you bring Maria behind the boss and then come back to me. I draw its attack towards me so you can fly safely."

"Why should I return? We'd already be both in range to scratch its back."

"I want to be there too."

"And who'd prevent it from shooting us down mid-flight?"

"Who says we two will fly?"

"I don't get it."

"Maria will be behind the boss, right? So you hit me a few times so that her [Trust Fall] triggers, I unsummon and resummon you two and we three will sit behind its back and it can do nothing about it. It is still just a wall after all. So no turning around."

"Please remind me to never anger you for real..."

We do as discussed, I fire a few spells at the boss and dodge away each time until Elly and Maria are behind it. Then Elly comes back.

"Are you ready, Jared?"

"Yeah, yeah, you can begin releasing some pent-up anger towards me, just don't overdo it."

"Anger? Me? Who do you take me for! But yes, I'll do so with pleasure."

"You little troll..."

"That hurt less than expected. That was almost pathetic, Elly."

"Yeah, yeah. Maybe you should double your CHA so I can gain a minimum of STR."

Three stabs later my vision goes white for a moment...

Then I'm behind the green wall. Just as planned. Then I unsummon and resummon Elly and Maria.

"Alright, you two, get to work!"

I bring out my claws to also deal damage with them.

"Aw, shit... Elly, can you borrow me a spear? Claws count as making contact."

"Oh, sure, here."

She gives me her weapon and then summons a new spear for herself.

I didn't expect my claws to already be almost twice as strong as the spear. Well, it is a +0 STR spear.

Hmm... I do have a +50 STR trash sword, how good is that without the training skill?

Ok, forget it, spear it is.

The rest are several days of casting spells, poking away with the spear and unsummoning my two minions whenever their SP is depleted then bringing them out again twenty hours later when they've recovered.

Since they are not 'dead' during that time I get my full MP maximum back so I lose only a handful of minutes on diminished MP recovery while they are out so they are a pure gain in damage output - as little as they contribute per hit.

"4̶̩̍9̴̨̾2̷̢͐0̴͖̀ ̷̙̇5̵̢̉7̶̽ͅ4̸̛̯9̴͎͛4̶̳̈c̷̞̕4̵̡̌c̷̟̀2̷̧̓0̵̥̅ ̴̺̿4̴̤̉2̵̣̃4̵͕̊5̶̂͜2̴͈͂0̵̗͒ ̵̤̍4̷̯́2̵̫̈4̷̥͑1̴̘̂4̴̞͘3̶̼̕4̸̡͋b̸̥͂2̸̝̽c̷̥͆2̸̜͛0̷̮̎ ̷̩͑5̴̧̌9̸̡͌4̷̣͌f̴͈̓5̴̡͋5̸͓̌2̴̡͗0̸͇͝ ̵̱̕4̶̟̒7̴̬̓4̵̧́f̸̰̄4̷̱́4̵̼͛4̸͔͝4̸̳̄4̷̧̓1̶̹͠4̴̼͘d̷̼̔4̸͠ͅḙ̴́2̵̲̍0̶̤́ ̴͑͜4̸̢́2̵̹̄4̴̦̈́1̷̳̎4̸̰̐3̷̈́ͅ4̷͓̆b̷̙͊5̵̩̽3̴͍͋4̵̫̈́3̴̘̇5̶̙͝2̶̫͠4̶̘̈1̷̢̃5̴̢͌4̸͇͌4̷̬́3̴͓͝4̶̥̌8̷̭͆4̴͙̎5̸͇͝5̶̝̉2̷͔̉2̸͎̒1̶̪͐2̷̜̏1̸̻͂2̵̺̐0̸͙͆ ̶̻͌4̵̨͊9̷͎̓2̶̫̾0̸͈͊ ̴̛̠5̶͓̇7̷̩́4̶̮́9̴̜̍4̷̛͚c̶̗̈́4̴̧̐ć̵̖2̶̯͗0̶̫͋ ̸͎͘4̸̧̿2̵̻́4̶̘̋5̶̮̓2̸̭͆0̶̤͝ ̴̫͒4̶̝͠2̵̮́4̴͕̅1̴̲̈4̵̦͊3̵̞̄4̶̟̀b̸̙̚2̴̻́1̴̞̿2̷͙́1̴͙̆ ̸̲́"

With that, the green wall crumbles and the door opens. Took only... four whole days. Still, what's done is done.

In the room behind the now open door lies the long-awaited exit portal... two of them in fact. Why, how?

(Did one of you spike my victory blood pack? I see double the exits.)

(Wasn't me, you Maria?)

(I wouldn't dare bring harm to you.)

(Ok, so both of them are real. And which is now the correct one...)

(Uh, good question, next question please.)

(I believe we should wait for the creature you call Dan. He might know the answer.)

(Right... I had almost forgotten about him. Rather I tried...)

"Hey, Dan, are you there?"

"One moment please, I'm almost done!"

(So that works at least.)

(But thinking about it, there being two exits just strengthens the theory that this is just two dungeons slammed together.)

(Possibly, but we're done now so that doesn't help us in proceeding towards our actual goal.)

After a few more minutes of waiting for something to happen, something does indeed happen. Dan's voice booms again through the room, "ok, now I'm finished. Oh, I see you're already at the exit. That was quicker than I expected."

"Quick? There was just a single obstacle left. And that took days."

"Yeah, right, so, emm... I don't know how to say this. I guess since you're here now that means this is goodbye for now."

"Well, yeah, if I had a clue why there are two exits or at least which the correct one is."

"From what I can see... both lead to the same destination."

"Works for me. Any last words before I leave?"

Dan has to think about it for a moment, "oh, right. There was something I wanted to give you. Uh, here."

"I hope I won't be this defective next time we meet but you... you did refuse to use the core to repair yourself so... well, we probably won't be able to talk like this again. But that ring should help with that."

"Uh, thanks, I guess. But do you even think you'll be in the state of mind to talk? I've read the description of the common monster skill and it doesn't sound like it."

"Well, there's only one way to find out, right? Ha~ha."

"Sure, well, see you next time then."

"Ok, bye~"

So far I've befriended a mansion, now befrienemied a dungeon, what's next? Dating a planet? ...wait, did I just call Lucia fat? Better not tell her that joke then.

I summon Maria as a bodyguard in case something waits on the other side then enter the exit portal.