Everything that happened at school followed step by step from what I remembered. The encounter with the student council at the gate, class lessons, lunch— all the same. Even though I had told Mio and Kana about my situation, it was like some cosmic force compelled them to stay on the path. They would only act differently if I threw a wrench in it.

For example, I knew Mio would try to stuff a piece of fried chicken dipped in Hatsumi's secret sauce into my mouth. She got sad when I dodged out of the way, and I didn't get horny around Kana in the bathroom.

"You've been out of it this entire day. Still on that time loop thing?" Kana asked after school while we were changing our shoes at the lockers.

"Yeah. I'd like for it to be my imagination. At the same time, I'm scared that the next time it resets I won't recognize it and be stuck like this forever," I answered.

"If I was stuck in a loop I'd be doing whatever I wanted because there would be no consequences. Things would eventually reset anyway. Maybe next time— if a loop really is happening— you can not think about changing me into a girl," he said.

My mind wondered back to when he was masturbating to me. For all his complaining, he didn't seem to mind the pleasures of his new body.

Kana had the right idea though. If consequences weren't an issue, I had free reign to do as I wish. But wouldn't I be resigning myself to this rewinding fate?

"In that case…" I texted Selene that I needed to study and wouldn't be coming in to help the kendo club. No sense in continuing to do the same thing. I should spend the time figuring out how to end the loop instead.

"Where are you going?" Kana asked as I changed back into my indoor shoes.

"The library. I'm going to see if I can learn anything." 

My best friend decided to come with me. Probably to stay by my side more than anything else. Mio was with the student council right now, so I sent her a message to join me later.

However, after spending an hour and a half reading scientific theories on time paradoxes, a seed of hopelessness began to grow in my heart. It was all passed off as a realm of science fiction. Few studies took it seriously.

I laid my head on the table with books stacked around me and sighed. Kana had his head buried in a manga from the start. It was a short two-volume manga that seems interesting enough to hold his undivided attention.

An idea came to me. I slipped my shoe off and rubbed his inner thigh with my foot.

"Uwah! Stop that!" His legs clamped shut faster than triggering a bear trap.

"You were so engrossed that I couldn't help but tease you." I stuck my tongue out. "I thought you were going to help me, but you're just here reading manga."

"Actually, this manga All You Need is Kill has a protagonist that reminds me of your problem," Kana said. 

My interest was piqued. Although I was skeptical about what we could learn from a manga, the realm of fiction might be the only place we can get an idea.

"In that case, now's not the time to worry about spoilers. Give me a quick rundown." I pulled up a seat next to Kana to see that he had been writing into a notebook while reading.

"The main characters Rita and Keiji are soldiers fighting an invading alien race. They end up trapped in a time loop, fighting the same battles over and over again. It turns out the aliens have what are called antennas that can send signals back into the past to learn and adapt. Both protagonists get their brainwaves caught up in the signals and become like antennas, so…" Kana hesitated to say anything further and bit down on his lower lip.

"Don't stop now. I really want to know!" I exclaimed.

"In one loop, they destroyed the alien antennas to stop the signals from being sent back into the past. However… Rita and Keiji, their own brains continued to function like antennas. Rita didn't give Keiji a choice and forced his hand to kill her so the other would no longer loop," he explained.

Both of us fell silent. It was horrifyingly tragic for them to fight together, and later learn that one had to die in order for the other to live.

Kana put the manga down and stared at his notes. "Hollywood made a film where both were alive at the end. Not as depressing, but both had its own charm."

I ended up borrowing the manga from the library and read it alongside Mio at home. We both had different feelings about the story but shared the same conclusion— the cause of my loop, unlike Keiji and Rita, couldn't have been from an outside force. Mio suspected, and though she was among those who still disagreed that a succubus could pull it off to begin with, that we were collectively the cause.

Mio and I sat on the bed with the Blade resting between us. It remained inert, unpowered since I hadn't had sex with anyone yet.

"What doesn't make sense to me is that it should have been out of juice. But I can't think of any other way this could have happened to ya," she said.

I was in agreement. The most powerful entities in this world were currently the Blade of the First Temptress and greater succubi.

"I remembered going to the convenience store with Kana and having a talk with him. Maybe my wish for things to stay the same resonated with the sword? But then where did it get the power to trap us in a loop?" I asked.

"When Bea had the sword, she eventually learned how to retain sexual energy. So she became like a second storage for magic. I don't think you're there yet though," she said.

If we went with the thread that I caused this, then I just needed to wish for my life to go back to normal. I knew for sure I didn't want to be stuck. Or maybe I just thought that way, but deep down I wanted to repeat this week?

Why? For what?

"Ugh… The more I think about this, the more my head hurts…" I groaned.

"Dinner's ready!" Hatsumi shouted from downstairs.

As I got off the bed my arm was pulled taut by Mio whose hardened expression, dented with uncertainty and the urge to say something uncharacteristic, kept me from leaving the room just yet.

"What's wrong?" I asked her.

"When you brought it up to me at first, I couldn't stop thinking if reliving the week is so bad. We get to be together forever, right? Then I thought— well, shit. I don't want to forget the other day when we were just laying together on the couch…" she said, tightening her grip on my hand as if I'd disappear once she lets go.

Mio's words cut deeper than a knife could. A dozen different Mondays flooded into my head, replaying the events of today but slightly different each time. They were beginning to mix together. What did I say last time? How did someone respond to me? Did I go to the bathroom now or later?

 I grew lightheaded and knees weak. If it wasn't for Mio holding me up, I might have fallen to the ground. She guided me back to the bed where I felt the cold steel of the blade at my palm.

For all the times I remembered, the others had forgotten just as many times. I wasn't the only one suffering. Mio didn't want to forget the time we spent together, and neither did I.

"It's okay," I began, squeezing her hand to reassure her. "Even if you don't remember after a reset, I'll remind you how you cheered me up ten different times. I can't forget all that you've done for me."

"God. It's your fault that I started getting mushy. Maybe next time me will start out with a sexual joke first." She grinned.

Selene was helping my sister set up the table downstairs. The savoury scent of curry permeated the air and made mine and Mio's mouth water coming into the kitchen. 

"I thought we wouldn't have curry until the end of the month? What's the occasion?" I asked Hatsumi, who was stirring the pot to completion.

"No occasion. I was just feeling curry tonight. Unless you wanted something else?" Hatsumi glanced over her shoulder.

"Curry's great! I'd never say no to that," I answered. 

The tradition was carried over from our grandparents back when we used to visit them the last weekend of the month. Their secret recipe was about the only thing that had made us look forward to visiting. Hatsumi appeared to have caught on to their recipe because it was a taste of nostalgia.

We didn't have curry last time. Did I trigger Hatsumi to act differently? I wondered to myself.

My restlessness was washed away as soon as I put a spoonful of curry into my mouth. The secret ingredients my grandparents raved so much about, I easily detected with my enhanced senses. It was cheese, added to thicken the curry base and make it more voluminous.

Now was no time to be lulled into complacency. I wanted to broach the subject to my sister, but not without sounding weird or putting her off.

"I was wondering if for winter break we could go to an onsen ryokan. It's starting to get really cold, and we can introduce our resident succubi to some hot springs of our world." I kept my head low and continued to eat curry, hoping to pass it off as casual conversation.

Hatsumi should answer casually as well.

However, when I glanced up, she was staring absentmindedly at her half-eaten curry in silence. Mio and Selene also turned to face her.

"Sis?"

She snapped back to her senses. "Oh, of course! Going to a hot springs resort for your winter break sounds like a great idea. I'll have to figure something out because my university work might get in the way."

Something about the hesitation in her answer caused warning bells to sound off in my head. She was distracted by something. Was it just because of her interview?

Hatsumi urged us to eat more curry because she had made plenty. We would even have some to take to school tomorrow.

We all retired to our rooms for bed, and I was left contemplating the odd reaction from my sister. 

"Winter break, huh… Would that even come for me when I'm stuck here?" I asked myself.

The door suddenly creaked open. The outline of a woman appeared under the frame and shut the door behind her.

"H-Hatsumi…?" My eyes adjusted quickly and saw that she was wearing see-thru lingerie. Her nipples were erect and the space between her crotch glistened from what little light was in the room.

"I did say I was going to surprise you." She winked.

As she approached my bed, I was trying to figure out what triggered this event. She didn't come into my room before. What changed? Just because of what I said in the morning?

Before I knew it, Hatsumi was by my side. She wrapped her arms around me, squishing my arm between her breasts and weakening my resolve to resist.

We had slept together many times as kids. When we became older and I was still a boy, she would often sneak into my bed to lay quietly by my side. But as I locked eyes with my sister, both of us in bed together once again, it seemed like our relationship as siblings was vanishing.

Before I knew it our lips had touched. My beautiful sister's tender expression warped into one of lust, tinted in the color of a woman in heat. She stuck her tongue in my mouth, drooling into my throat between our sloppy kiss and panting.

"Tell me you love me," Hatsumi pleaded.

I swallowed hard, feeling mine and my sister's hot saliva slide down my throat. "I… I love you, sis…"

It was like a trigger that flipped the switch inside her. Hatsumi climbed on top of my waist and dry humped me as though I had a dick.

"Mmm… Saeko~ if only you were still a boy. I'm sure we would be so compatible with each other. But that's okay. I still love you so much, my dear Saeko~" she cooed seductively, causing goosebumps to form on my skin.

Just who was the succubus here? I thought to myself.

The light fabric of her lingerie was all that stood between us. Our breasts squished together as she hugged me tighter, engulfing me into her embrace. Hatsumi was gushing wet and soaked the sheets under us.

I pushed myself to a sitting position and returned the embrace. While in each other's arms, lips and tongue connected, bodies undulating back and forth vying for control, her lust began to overwhelm my sense of reasoning.

Hatsumi was so hot. That voluptuous body of hers, which had belonged to Kotaro for a time, was now mine to taste. We had sex once before, but Mio played a part in influencing that to happen. This visceral joining was by her own choice.

At some point, my legs had intertwined with hers. The little nubs above our soaking pussy, the clitoris that brought so much pleasure when masturbating, began to rub against each other. Hatsumi put a hand behind my head and pulled me in for another kiss.

Pleasure was everywhere. 

My clit, my lips, my breasts. We were two flames that merged and became an inferno.

"Am I making you feel good?" Hatsumi asked, her hot breath was like a sauna to my body.

"Yes… It feels good… too good… mmhh!" I moaned.

"Hehe… I'm your big sister after all… I know everything there is about your body. Oh, I love you so much. Show me your cumming face, please?" she begged.

Nothing about this was right. We were siblings. We had already crossed the line once, but to do it a second time and while in control of our mental faculties… There was no excuse.

Yet while partaking in my sister's lust, seeing her eyes wide as though to capture every second of our act like a camera, tongue hanging out and drool dripping down to our crotches to mix in with the juices, I couldn't stop. I wanted to continue fucking my sister, and I wanted my sister to continue fucking me.

My tail emerged, whipping back and forth with excitement. I pressed it between our legs, soaking it in our juices until it was sufficiently lubricated, and entered my sister's pussy.

"Aaaahhhh! Yes! Saeko~ more… your big sis wants more…" she pleaded, and I obliged.

Pumping my tail into her like it was a penis, Hatsumi threw her head back and screamed hysterically. I'd never seen her like this before. So lost and abandoned to the thrill of sex. I didn't know how to feel about this side of her, but this wild woman was no longer just my sister— she was my woman and bitch now.

Not wanting to wake the house up, I pushed her onto her back and screwed my lips shut on hers. Our tongues danced a passionate tune, drooling into each other's throats for a taste.

Wet shlichking sounds grew louder as she became more wet, and I quickened my tail's pace. Hatsumi's eyes rolled to the back of her head. If I pulled my lips away, she moaned incoherently.

Hatsumi, my older sister who I always viewed as a role model and a hardworking woman, was reduced to a sex-crazed mess because of me. Perhaps this was meant to be. How better could I reward my sister who was obsessed with me than to give myself to her?

I flipped us around to the sixty-nine position. My tail continued to penetrate her while I licked and teased her clit. Her moans were muffled, buried under my pussy as I rubbed it in her face. 

Why did my sister of all people taste so good? The sexual energy I got from her everytime she orgasmed was of such high quality and on par with Kana.

Everytime her tongue brushed against my clit, I wanted to let my voice ring out and demonstrate to her how good I felt. Both our bodies began to tremble, hers more intensely than mine, I hooked my arms around her legs and ate her pussy out to a quaking orgasm.

"You're making me cum, Saeko— Ahh! I'm cumming! So good— aaahhhh!"

Her lust flowed into my very being, filling me with sexual energy more delicious than anything I had ever tasted.

We remained in each other's arms, our lips never parting unless to take a breath. When at last she became too tired to indulge in our immoral romp, the sexual trance vanished and her demeanor returned to the sister I knew and loved.

"I didn't know you can be so naughty, and it was so much better than our first time." She smiled warmly while stroking my arm.

"When you came in dressed like that, I couldn't help it. W-Why did you suddenly come in anyway?" I couldn't so much as glance away since we were face to face in bed.

"I just want to be with you. I can't stand being apart from you. My paradise is whenever I'm by your side," Hatsumi answered as a matter of factly. It sounded like a confession of love. I trembled at the resolve in her voice not out of fear, but at sheer awe that she could say something like that.

To me, who was once her brother and now sister, never once shared her feelings. Not until I became a succubus. If we weren't siblings, I wondered if things would be different between us. Reality was cruel. After tonight, we had to go back to being siblings. Hatsumi wanted something more, and I couldn't reciprocate it.

She must know that.

It pained my heart to be with her like this. I was myself as dangling bait above the pond, and she was the starving fish. Everytime we kissed, had sex, or I humored her advances, I lowered the morsel a bit to tempt her only to yank it away. 

Are you okay with that? I asked Hatsumi in my thoughts. She had already fallen asleep with a satisfied smile on her face. Perhaps she had caught the bait in her dreams.

I leaned forward to give her a kiss on the forehead and, unable to control myself, once more on the lips and whispered, "Night, sis. I love you, too."