Finally, after a year of diligent research and hundreds of failures, Arthur and Tamayo achieved their long-sought goal of developing a formula capable of transforming the undead into demons.

"Hah, for creating this we have worked really hard, Tamayo, and the result is not bad," Arthur said as he held a vial containing a green liquid in his hand.

They've long since dropped the honorifics while referring to each other.

"Honestly, I didn't expect that we'd be able to create it so soon. It was only possible due to your knowledge and equipment, and also due to the research data that your secret companion provided." Tamayo added.

Yeah, Shizuka also helped in providing research data for Arthur and Tamayo. Shizuka also had access to the old research archieves in the Butterfly Mansion, so she would give him the relevant files when needed.

The result of everyone's hard work was standing right in front of them, a female undead now turned into a demon.

She looked like a woman in her twenties and was wearing a white sundress, her skin had regained most of her brilliance but still had an almost unnoticeable greyish hue.

The decayed skin and rotten parts were regenerated, her figure was even enhanced in all the right places, her ears became pointy and she had also sprouted a tail and a single horn on the left side of her forehead.

With her beautiful face, she looked like a typical succubus, but without wings.

But she is still undead, though genetically enhanced.

And since she's an undead, she is under Arthur's complete control.

"Can she speak?" Tamayo asked.

"I don't know, let's find out." Arthur turned to the undead woman. "Can you speak?"

She nodded in affirmation, "Yes, Master, I can speak."

'Is this undead blushing just because I talked with her?' Arthur pushed this observation to the back of his mind and turned to Tamayo with a grinning face.

"Well..." he was too elated by the success of the serum. "She can!"

The demonification of the undeads made them capable of proper human speech and logical thinking. As for their strength, he'll have to test it.

"But is she still capable of surviving in the sun?" Tamayo wondered.

By now, Tamayo knew everything about undeads, or at least as much as Arthur did. So naturally she knew about the fact that undeads weren't hindered by the sun.

"Hmm, let's find out that too." Arthur turned back to the horned demonized undead woman.

Spoiler, she was disintegrated.

"Fuck it, and she was quite beautiful too, we will miss her." Arthur sighed.

Tamayo smiled, "Sorry for your lose, Heito."

Arthur chuckled, 'Did she just go along with my joke? She never joked before, was it her opening up to me? Really?'

Sighing again Arthur spoke, "How about we celebrate this success, there's even a summer festival ongoing, how about we check it out tonight?"

Thankfully, Yushiro wasn't here or he would've jumped in fury at Arthur.

"Uh," Tamayo hesitated, she can't enjoy herself when she could use that time to research Muzan's curse-breaking formula. "Sorry, but I'll have to decline."

"Oh, I insist,"

"But-"

"I won't hear more, you're coming with me and that's final."

Tamayo sighed as she gave up, she has learned to give in to Arthur's persistence sometimes. "But we have to return in an hour."

"Sure, and here, you can wear these." Saying so, Arthur brought out a makeup kit and a beautiful violet Kimono with gold embroideries. It was one of the most expensive ones that Arthur had stored up in his inventory.

 He had lot of them rotting in his inventory. A LOT of about everything. Five years in the HOTD world wasn't just used for fucking Shizuka's and Saeko's brains out, after all.

Tamayo already knew about this unique ability of Arthur to summon various items from different dimensions but she was still amazed by the quality of the kimono.

"Is it really fine for me to wear this?" She asked.

Arthur just smiled, "Of course, it's fine."

.

.

.

"Uh, Tamayo-Sama? Heito-San? Where are you going?" Yushiro asked as he looked at Tamayo wearing the violet kimono with beautiful golden accents and embroideries. Heito was also beside her in a black suit.

'Are those tears?' Arthur looked at Yushiro.

"There is a festival going around the town, we're just going out to explore the shops a bit," Tamayo replied.

{Hehehehehe Cuck him, Arthur. Fuck Tamayo right in front of his eyes, jajajaja} Barnes's voice rang out in his mind.

{Barnes, it's not cucking. He's not in a relationship with her.}

{And besides, I don't even think that it's pure love that he's experiencing. I think the method Tamayo uses for demonification, somehow enchants the demonified being into 'loving' their masters... You saw how that undead girl blushed, didn't you. It's still just a theory though. }

{Yeah, yeah whatever you say. But it's fun, you're finally fulfilling another one of my dark fantasies! }

Arthur held in a sigh at Barnes's antics.

"We'll return in just an hour, so keep an eye on the estate, Yushiro. And don't fight with Ryoma-Kun." Tamayo instructed Yushiro like he was her little child.

"Y-yes, Tamayo-Sama." Yushiro replied, though completely shaken up on the inside.

Arthur noticed Tamayo's expression as the interaction happened, she ignored the guy's feelings like nothing. It was as if... she was feeling sorry for him, for having those feelings towards her. As if... she was just exhausted by his feelings.

'I see,'

After leaving the house, Arthur and Tamayo roamed around the festive town, seeing the vibrant lamps in the shops and crowds of people. They soon reached the shrine though Tamayo didn't want to offer a prayer, she told him that she'd just watch from afar.

When asked the reason, she replied, "As a demon under Muzan's control, I have murdered countless humans and even after freeing myself from his control I have taken human lives. I don't deserve to ask for happiness or even forgiveness from god."

"I see, then how you ask for happiness and well-being for the rest of humanity from the god?" Arthur suggested.

"Um," She was speechless.

"So, how about it?" Arthur asked again, "Let's offer up a prayer."

"Okay," Tamayo replied though Arthur could still sense some hesitation from her.

They both walked to the front and offered the prayer in the traditional Japanese way.

After that, they explored the attraction of the festival. He spotted Tamayo smiling genuinely many times during their time.

"Ah, looks like we just have a couple of more minutes till the hour is complete." Arthur sighed.

One hour for an outing can feel rather short or possibly too long if the company wasn't right.

For Tamayo, the beginning felt dragging since she just wanted to go back but now... she felt complicated.

'No, I should focus on my research on upgrading the formula.' She thought.

Arthur looked at Tamayo's ever-sad eyes, 'If our relationship was a bit closer then I would've probably taken you above the sky and let you watch the cityscape from the clouds. And then when you'd be lost in the moment, I'd kiss you. That'd be A perfect romantic date.'

'But... that's just too forceful at this moment. I don't want to push her away.'

Well, yeah. Arthur has come to love the lady over the past year. He wants to give her happiness, new dreams, a life where she's capable of laughing without restraint, and a life where she doesn't have to constantly think of just killing that overpowered narcissistic demon.

'Oh well, time to head back I guess.'

'And I'm horny, maybe I'll visit Shizuka today, her big melons are a blessing to me.'

===========

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