https://www.dmm.co.jp/dc/doujin/-/detail/=/cid=d_672304

This is related to that Banana's series about Asuka the gyaru who hooked up with her former Highschool boyfriend and porn actor Ren as payback for her husband Yuuki once cheating on her, in the sequel where Asuka leaves Yuuki for good another girl is it introduced, Mitsuki Shiina, who participated in a threesome scene with Yuuki and Ren. This is Mitsuki's side of the story.

Mitsuki Shiina was already introduced before, she was Asuka and Ren's Highschool friend as well, Mitsuki was Ren's side piece back then so when Asuka left Ren because she was tired of Ren not being committed, Mitsuki kept being Ren's woman for years all the way the till now.

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Here we find out Mitsuki is married to Yuto Shiina, who despite being 30 years old, five years older than Mitsuki, he has some developmental disorders, Yuto is a little slow, mentally underdeveloped for his age but he is the heir of a wealthy family, owners of a large company, Yuto's development issues aside he still works at his family's company, he is their heir still, even with his slowness he can still work, within his limits.

While Ren and Mitsuki are fucking literally behind his back, Yuto gladly smiles at his friends, happy that Ren is visiting too, yes Ren is also Yuto's old friend, actually it was Ren that introduced Mitsuki to Yuto and the two hit off from there, eventually marrying each other; looking at how his friends are so kind to hang around with him, Yuto decides to procure a method to cure himself of his development issues.

Upon visiting a doctor Yuto is given bitter news, yes there is a surgery that could visibly enhance his brain to develop but it is a very experimental procedure, the effects are not permanent, Yuto could revert to his former self in matter months but Yuto is determined to go through it, he loves Mitsuki and wants to actually hold meaningful conversations with her, sure Mitsuki supports Yuto's decision but in truth Mitsuki never loved Yuto, in her private thoughts she loathes him, Mitsuki really sees Yuto as a piggy bank she fished on Ren's recommendation.

When messaging Ren about Yuto's surgery, he expresses some worries but Mitsuki says they just need to be more careful about their affair for a 6 months or so, that's the expected timeframe the doctor has warned Mitsuki that her husband's enhanced mental capacity will last.

Yuto indeed grows smarter, he starts talking more responsibilities at work and feels he can act cooler around Mitsuki, she feigns being proud of him; then Yuto starts to notice Mitsuki acts quite strange around him, he just never noticed before, it is upon witnessing the completely neglected bouquet of flowers Yuto once gifted her that Yuto starts recording his suspicions, one page at a time, to a point he really hired private eyes to confirm it all, Mitsuki and Ren have been fucking behind his back when before the marriage, Yuto was never their friend, he was their personal clown, once Yuto understands his situation he cannot bear his pain.

Mitsuki comes home as usual, just saying she is back from being with friends, Yuto is ready to confront Mitsuki over her diabolical true self, she doesn't waver at all as Yuto's current stress only hastened the effects of the surgery waning, today is the day Yuto's condition completely falters, reverting his mental capacity to its normal, underdeveloped self, Mitsuki just calmly talks to Yuto like a child, there's no need to be afraid, you aren't lonely anymore; Yuto just cries like a big kid, saying Mitsuki is so kind.

His inner thoughts become infantile again, recalling his time as feeling super smart but now that is no longer the case, and Yuto doesn't mind much anymore, Mitsuki is by his side and that's all that matters, in that very moment Mitsuki got Yuto to sign a document concerning a huge transfer of money, about 200 million yen. Afterwards, Mitsuki says she wants to go for a walk, Yuto happily says he wants to go too! Mitsuki takes him, once Yuto sees a flower shop he asks Mitsuki to wait a little, he wants to buy some.

Mitsuki messages Ren, the transfer went through, nice! Yuto comes back, with a bouquet in hands he cutely gifts Mitsuki with it, saying it is for her, Mitsuki smiles proudly complimenting Yuto for being able to buy it by himself like a big boy. In his thoughts Yuto is proud of himself, Mitsuki seems so happy with her flowers, he did a good thing; however, in a tragically poetic thought Yuto remarks those flowers looked lonely so Mitsuki's smile will compliment it! In his final diary entry, the one where Yuto was slowly recording his development after surgery, he just writes he thinks he is happy... THE END.

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I tend to grade Netorare works with varying levels of humiliation porn, some don't have the betrayed MC suffering much, while others have the MC be absolutely destroyed for sadism's sake, this one is pretty high on that end. Much worse than Asuka's side since there you could see how Yuuki's mistakes led to his downfall, here though, Mitsuki is just plain evil and her husband Yuto is a victim through and through, poor dude.

Will this have a Part 2 like Asuka had? Time will tell. Anyway, Banana says this was based on Daniel Keyes' Flowers for Argemon, indeed, the setting about mental development surgery is taken straight from it. NTR authors want to flex their literacy sometimes it seems.

Base +21, hobohobo +43, Fofotron +28, tim_4519 +5, laccob83 +12, Coledas Ukgent +19, Asarta +6, your_name +6

https://www.dlsite.com/maniax/announce/=/product_id/RJ01476918.html

Base +30, wavedash +22

Wouldn't his family know he has issues and thus have someone check up on him? It just seems weird for her to get away with it. Then again it happens in real life all the time so this is a ntr that is tragic as fuck. A good story that honestly didn't need the ntr but, compliments it so damn well. Good shit

Base +8, Wilfriback +23, Asarta +6, sike69 +10

The other series official title is "Wife With an Attitude Fucked by Her Ex" or unofficially "Ex-Delinquent Wife Gets Cucked" in case anyone was wondering

Base +5

太出生了这女主和黄毛

Base +4, byedark +6

Well, I'll give the author credit for mixing it up. Normally NTR cucks simply act retarded, but this one is clinically diagnosed. That said, when his family finds out about the huge financial transfer, wouldn't they start to meddle? They might even be able to have it nullified if it can be proved that he was mentally incompetant at the time of signing it over.

Then again, this is NTR World, so odds are the MC would sooner get hit by a bus chasing a bouncy ball and die, having already left behind his family's company to her so she and Ren can live like rich douchebags (Ren would still sleep with other women behind Mitsuki's back, most likely, since they're both scumbags)

Base +6

求汉化，完美诠释出轨人妻的神本

Base +6, byedark +6