Shido and the girls had been living in the Spirit Mansion for a little over a week now. Overall, things were going reasonably fine.

They were training every day, and were making fair progress, partially also thanks to Marina's events, which now guarantees that even the girls who don't have Spirit CR-Units have at least 10% compatibility. And about those events, while Shido and the girls have been getting more used to them, Marina, and sometimes Maria, still surprise them with their ideas.

Today though, things were going mostly fine. Nothing noteworthy had really happened, and even the event chosen for today was really simple.

"Are you two sure you're fine?"

"H-ha! This is nothing."

"Reassurance. It's a bit embarrassing, but it's fine."

It was quite simple, Shido had to take a bath with the Yamai twins.

Over the past week, he had already taken baths with the girls many times, probably more than he has bathed alone to be honest. Compared to when he was told to bath with Miku and almost had his family jewels crushed, or when he was told to thoroughly wash Yoshino and Natsumi and that made him feel incredibly guilty, this was rather easy.

Thanks to everything that had been happening in the past week, Shido hardly went into a panic just by having a naked girl nearby now. They washed themselves rather uneventfully and now they were relaxing in the bathtub together.

The bath was big enough that they could sit beside each other. Shido currently had a flower on each arm, quite literally, since he had an arm around each sister.

On his right was Yuzuru, her calm expression was really relaxing and her big breasts floated, giving Shido a better understanding of buoyancy than any class ever did. On his left was Kaguya, whose cheeks were red due to embarrassment and her breasts… were not like her sister's, but were still erotic in their own way.

Of course, there was only one way Shido's body could react, and by now he knew it was pointless to try and hide it, though he still found the stares a bit embarrassing, but he couldn't really complain when he wasn't really hiding his gaze. And holding them in his arms means that his ability is working perfectly.

While everything was fine as it was, it was also somewhat uneventful. Maybe thinking the same, Marina decided to spice things up.

[Yeah, this is kinda boring. Shido, why don't you help them wash themselves? How about a competition to see who ends with the highest compatibility?]

"... Alright."

Shido felt like he wanted to complain, if this is what she was going to go with, why wait all this time? They had already washed themselves once, so this was just a waste. But it's not like he could say that.

Unknown to him, it was actually Kaguya and Yuzuru who had asked Marina for some alone time with Shido so they could try to get their Spirit CR-Units. Although they didn't know what exactly the AI would prepare for them, they were more aware of the real purpose than Shido.

"Alright, let's do it."

"Provocation. Yuzuru won't lose."

But, now that Marina had put it as a competition, the twins didn't feel like losing to each other.

Each one sat on a stool and were waiting for Shido, who was slightly impressed with how much they looked alike from the back and with their hair tied up.

In any case, Shido decided to just get on with it. As he spread the soap on his hands, he decided to begin with Kaguya.

"Hyaa!"

She was surprisingly startled when Shido touched her back, even though he really didn't do anything more than just that. She apologized for that and then told him to continue.

When a woman washes the man's back, the first thing that comes to mind is using her breasts, but the same isn't true the other way around. Sure, Shido could spread soap on his chest and use it to spread the soap on Kaguya's back, but that would hardly feel good for anyone. All that's to say that Shido was simply washing Kaguya normally.

But of course, they needed to be relatively close for him to wash her. Maybe because of her nice smell, maybe because he had been looking at their breasts before, maybe it was his lust building up all this time, or most likely all of that, Shido was having trouble keeping his rational thoughts going.

He looked at Kaguya's nape. It wasn't a part he usually saw or paid attention to, and because of that there was a strange eroticism to it. Shido couldn't hold back and kissed Kaguya's nape.

"Kyaa, y-you startled me, Shido."

"S-sorry, I didn't mean to. I just… couldn't hold back."

"Surprise. Yuzuru knew Kaguya was enchanting, but not this much. You have really grown."

"What are you even talking about?! Ahn!"

Shido continued washing Kaguya, and she continued letting out some occasional moans. It seems she was quite sensitive, especially so around her butt and the side of her waist.

He was soon finished with Kaguya's back, and figured he wouldn't keep Yuzuru waiting any longer, so he began washing her.

"Oh, I thought you'd also let out your voice."

"Superiority. Unlike Kaguya, Yuzuru is a proper lady, she won't let out a weird voice."

"Hey, what's that supposed to mean?"

Kaguya didn't seem too happy with Yuzuru's comment, but Yuzuru pretended she heard nothing and Shido figured it was best if he ignored it as well.

Before, Shido had thought that these twins were basically indistinguishable from the back, but now he realized he wasn't quite right. Now that he had gotten a good loop up close, he could tell that Yuzuru's back at least seemed slightly bigger, and her skin felt more springy to the touch, likely because of subcutaneous fat.

"Mmn…"

Although Shido wouldn't say it in front of Kaguya, if he had to pick a favorite, it would be Yuzuru. It was probably just his personal preference for more curvy bodies speaking, but washing Yuzuru felt much more erotic. Her skin felt nice to touch, being able to see her breasts from behind was erotic, her butt was soft, and her smell was nice.

"Nnn."

"Um, Shido?"

"Huh? O-oh, sorry. The smell was so nice I kinda got lost in it."

"A-aan."

Without even himself realizing it, Shido had been sniffing Yuzuru's neck. Although it was really nice for him, it was probably uncomfortable for her. Though maybe not, since she did let out a moan there.

"No, that doesn't really matter. It's more, um, that."

Shido didn't understand what Kaguya was talking about. But he soon did once he thought he should wash (grope) Yuzuru's butt a bit more before finishing.

When he closed in to smell her, he ended up rubbing his member between her butt, and at some point began to move involuntarily. It's no wonder he was feeling really good down there. There was some liquid on Yuzuru's back, but it wasn't white so Shido could feign ignorance.

"S-sorry. I, um-"

"I-it's fi- forgiveness. It's fine."

Shido noticed that Yuzuru almost broke character there, but he was a bit too embarrassed by what he'd just done to comment on it.

He was done with both their backs. Although he had an idea, Shido figured he should ask to confirm.

"Um, how much should I wash?"

[Of course, everything. Every nook and cranny. Get your fingers in there if you must.]

Shido felt like Marina just gave up at the innuendos there at the end, but he still just let out a sigh and continued doing as he was told. Needless to say, now he had to wash their fronts.

Shido figured he might as well start with Yuzuru. Not only had he started with Kaguya before and Yuzuru was closest to him now, but there was another, or rather two, big reasons for Shido to focus on her.

"*Stare*"

"E-embarrassment. Shido, you're staring too much."

"S-sorry, it's just… it's kinda hard not to."

Of course, those were her breasts. Ranking among the biggest in the Spirit Team, Shido wouldn't be a man if he wasn't hypnotized by them. Just the size, which made Shido unsure if he could grab them completely using one hand each, was already something, but that wasn't all.

Naturally, the pink areola and nipples were in proportion to the breasts they were the tips of, which means that they were also quite large. Shido couldn't help but admire how they puffed out and made their presence known as he touched Yuzuru, and he may or may not have let his fingers rub an inappropriate place to see how she would react.

"M, mmh."

Shido washed most of Yuzuru's body, only breaking eye contact with her breasts to look at her blushing face. That made Yuzuru more embarrassed, which made Shido think she was even more cute, which made it harder for him to control himself.

Eventually, the only place left to wash were the breasts. Although Shido would love to continue, he didn't want to make Yuzuru feel like she was being forced.

"Yuzuru, what should I do?"

"P-please, Shido."

"Got it."

At this point, Yuzuru was in the same situation as Shido. She wasn't even in character anymore. They were too excited to stop.

"Ahn!"

Shido grabbed Yuzuru's breasts, the guise of washing was no longer in their minds. Shido just wanted to grope those big breasts, and Yuzuru just wanted to feel good with Shido's hands.

Using everything he learned with the other girls, Shido groped and played with Yuzuru's breasts. Although he didn't yet know where Yuzuru liked it, he knew that places not often touched, such as the underside, tend to be more sensitive, so he decided to begin with those.

"Hm, here?"

"A-aaah!"

"E-eh? Yuzuru?!"

Of course, Shido didn't contend himself with so little. Although he himself had yet to realize it, finding the girls' weak spots was becoming one of his favorite pastimes.

It didn't take him long to figure out that Yuzuru liked having her breasts squeezed, and while it might appear obvious, it seems that her areolas and nipples really were the places where she felt it the most.

With that information, the only thing left for Shido to do was to make the most of it.

"Mmn! Nnn! W-wait, Shido!"

Shido was having fun playing with her nipples in all sorts of ways. It seems that Yuzuru was quite enjoying him flicking them. Of course, he didn't forget to also grope the breasts from time to time, the unpredictable stimulation made it all the better.

Part of Shido wanted to try sucking in Yuzuru's breasts, but he decided to hold back. He didn't have enough courage at the moment, and it was something to look forward to in the future.

So for now, he would content himself with just playing. Shido lost himself for a few minutes. He was fully concentrated on his hands, with Yuzuru's moans acting as background music.

After a while though, he did remember the situation they were in, and decided that it would be rude to ignore Kaguya any further.

"I guess it's your turn now, Kaguya."

"E-eh? W-wait, please wait. I-I've never seen Yuzuru make that kind of face or voice before. I-I'm a little scared."

Kaguya suddenly stood up, as if a monster from a horror movie was coming in her direction. Shido didn't really understand what she was talking about, so he turned around to look at Yuzuru.

Yuzuru's shoulders and chest were moving, she was breathing hard. Her body was also shaking lightly. However, once she noticed Shido and Kaguya, she simply showed them a thumbs up, so Shido guessed that, whatever was going on with her, she was fine.

Although Kaguya still seemed a little scared, she seemed to have resigned herself. She didn't want to lose to Yuzuru, even in this. That was good, because in his current situation, Shido might have seriously chased her down.

Having closed in on Kaguya, Shido began to touch her body. It was unclear whether he remembered the whole washing thing or not, but he was definitely touching her all over.

"M, mmh! S-Shido. Aan!"

Since Kaguya was more sensitive than Yuzuru, or at least showed it more, she was more fun to tease. Even the lightest touch made her let out a beautiful sound.

However, due to everything that had been building up in Shido for a while, he was unable to hold back anymore.

"Ah, screw it."

"Mhh!"

Shido kissed Kaguya. She was surprised at first, but soon also lost herself in the kiss. It was her first, and while Shido might have been a little forceful, it was not unenjoyable for her.

Needless to say, Shido did not forget to move his hands while kissing. He got both hands on Kaguya's ass and began to grope her.

"Mm, nnh!"

"Sorry, I couldn't hold back. I'll stop if you want me to."

"D-don't make me say it… just keep going."

Although Shido apologized, now for the nth time, it seemed Kaguya didn't mind it, so it seemed that they could enjoy themselves a bit more.

They kissed for a while more, and Shido made sure it would feel good for Kaguya. But then, an idea came to his mind. Although Kaguya's breasts aren't as big as Yuzuru's, what if they had the same weakness? It was worth trying.

In reality, Shido just wanted an excuse to touch her breasts.

"An! W-wai, mmh!"

It seemed like Shido had hit the jackpot. In fact, because of Kaguya's reactions, she was more fun to tease than Yuzuru. She was moaning so much that they couldn't even continue their kiss, although Shido simply opted for kissing her neck and collarbone instead.

Shido would spend the next few minutes playing with Kaguya's breasts and nipples, until…

"Complaint. This is unfair. Give Yuzuru some attention too."

Having recovered, Yuzuru walked up towards them. With the way she leaned her body, purposefully pressing her breasts on Shido, it was clear that she still wanted more.

"Yeah, sure."

Shido was in no state of mind to refuse. He pulled Yuzuru close and began to kiss her as he continued playing with Kaguya. Then, after a while, he switched, groping around Yuzuru's body while he kissed Kaguya.

"Mmnh~"

"Nn, mmh~"

Surrounded by the twins, Shido felt like he was in paradise. Their soft bodies pressing on his, he could grope their breasts and asses to his heart's content, and their kiss also felt so good.

Kaguya and Yuzuru also found this surprisingly enjoyable. All the experience was slowly making Shido into some kind of master. His touch and kiss was slowly becoming irresistible.

They felt like they could enjoy this forever, and they probably would have, if they weren't interrupted by Marina.

[Wow, this went much better than expected. Sorry to interrupt, but you guys have been in here a while and I don't want you getting sick, so it's about time to wrap it up.]

In reality, Marina was ignored after she said this, but then she tried talking to them a few more times until she gave up and blasted an alarm as loud as she could. Only then did she manage to get their attention.

Kaguya and Yuzuru got a little embarrassed and went to properly wash off so they could leave. Shido also went to his corner, though his objective was to relieve himself. After everything, he felt like he was about to burst.

… Neither of them would say a word about it, but both Kaguya and Yuzuru watched Shido relieve himself, trying to disguise their gazes while their faces were bright red, which is why Shido finished before them.

"U-um, I'll be going out first."

With his capability of rational thought returned, Shido also felt a bit embarrassed by what they were just doing, so he quickly excused himself.

Once he left, the twins' curiosity got the best of them and they decided to investigate the corner where Shido had been. Of course, they looked for Shido's "evidence" and then it was their turn to relieve themselves. It took them a few minutes to leave after that.

"Kaguya."

"Yuzuru."

""... Yeah…""

Although this happened because of Kaguya and Yuzuru asking Marina for a chance to get their Spirit CR-Unit, they did not regret it in the slightest. Rather, if they had any regrets, it was that it had taken them so long.

The twins were looking forward to the daily maintenance of Shido's ability.