Kono S wo Mi Yo

Rin Usuda is a troubled young man. He has a problem with his ass. Or rather, the funky birthmark on his ass. You see, his childhood friend Makoto Ikaruga used to tease him about it, leaving a deep-seated trauma that will cause him to barf on the possibility of baring his ass. Yes, Rin will even barf on the prospect of baring it to other guys, which is quite a problem in Japan since bath-houses and onsen are entered in the nude.

Another problem is that Rin has a massive crush on Chizuru Izumiya, a relative of his. He even frequents the hospital she is working in, if only to have late night coffee. Some nurses have even knew the boy.

Will this impasse bounce back-and-forth throughout the story? Hell no.

Kono S wo, Mi Yo (This S, See It!) is a manga written by Taku Kitazaki, and published by Shogakukan.

Tropes:

• Blackmail: Takako used the "sex tape" kind on Kei Kurou and Mio Abiru. Of course, Rin is in on it too.
• Blessed with Suck: Rin. His birthmark causes women to madly fall in love. Not with him, with his manhood. Once said manhood enters the woman's womanhood (Ayumi did give Rin a blowjob and she's still affected), the affection ends and the affected woman loses awareness of the birthmark's power (meaning they can never be affected again)... sometimes with disastrous consequences. Sort of similar to Diarmuid's Love Spot in Fate/Zero, only much less permanent. Oh, and the birthmark does not work on animals, children, and women past their prime; this comes to bite Rin on the ass later.
• Chick Magnet: Rin, if he ever bared his ass in front of many women. Which he did, due to Takako and Kei's machinations.
• Cool Big Sis: Chizuru. Chizuru's fiancee fits the mold well, too...until he is revealed to be a Bitch in Sheep's Clothing who slept around with different women behind her back.
• Christmas Cake: Chizuru's 30 and still single. She's soon to be married though... well, things get complicated with Rin around.
• A Date with Rosie Palms: a young Chizuru unknowingly touched herself whenever she stared intently at Rin's photo when he was still a boy.
• First Love: Chizuru is always in Rin's mind ever since he was young and vice-versa.
• Green-Eyed Monster: Chizuru. When Makoto texted her that Rin got a girlfriend in a flashback, something inside her broke. Cue Chizuru's green eyed monster unleashed. Her jealousy reared its ugly head again when she learned that Rin lost her virginity but she barely contained it despite the fact Makoto called her on it. Makoto also gets a shade of this when she learned that Rin slept with Lisa to get rid of her stigma.
• Hospital Hottie: Chizuru, Ayumi Kamon and Lisa Tokiwa.
• I Didn't Mean to Turn You On: Ever since Makoto saw Rin's stigma without him knowing, every close interaction with him results in her hormones going to overdrive, just barely controlling herself. Even thinking of Rin makes her panties wet.
• Interrupted Suicide: When Lisa Tokiwa wants to commit suicide by jumping off the hospital building (with only Takako desperately holding on to her), Takako tells Rin that he must use his stigma in order to save her. Having no choice, he shows it to her and thus claiming another victim to the stigma.
• May-December Romance: There are lots of Rin/Chizuru hints.
• Manipulative Bitch: Takako Washio. She used Rin's birthmark to increase her social standings.
• Parental Issues: Chizuru's lingering feelings for Rin is deeply rooted in her dysfunctional household, particularly her relationship with her father who looks like Rin as an adult.
• Patient Childhood Love Interest: Makoto.
• Porn with Plot: Arguably heavier on the plot side.
• Power Tattoo: Rin's birthmark is a tad too elaborate not to think of as this.
• Relationship Sabotage: Chizuru hides her feelings for Rin by saying that he's nothing more than a brother to her and then says that there's a possibility for them to be together and then backs out at the last minute. This of course hurt Rin considerably.
• Shout-Out: AKS 74.
• Tall, Dark and Bishoujo: Kei Kurou. Well, until she saw Rin's birthmark that is.
• Teen Idol: Mio Abiru.
• The Vamp: Takako is fast heading down this road, although she did this by proxy.
• Woman Scorned: Chizuru's mother became this when she caught her husband having sex with another woman in her own house. Complete with a Kubrick Stare.