Honest warning, the story isn’t complete (noticed the “1” in the title?), and you’ll be left wanting for MORE! MORE!! Because, man, it is interesting, and the art is simply gorgeous.
In a nutshell: we follow a male highschooler, he looks the decent guy, although he’s a cold beast in bed, his girlfriend enjoys his non-expressive side. There’s a reason he looks so composed, mature, and is able to keep a lid on his emotions, he’s been marked by a end of childhood experience, his older female cousin introduced him to sex too early and he still can’t come to terms about the event: trauma, good thing?
The female cousin comes back in his life, she’s a teacher in his school, and the guy will endeavour to ignore her seduction attempts while banging his GF harder than before, to try and forget… And yet, clearly, there’s more at stake.
If or when more is released, I’ll share it, until then, enjoy, it’s already great as it is, thanks a lot to Hive-san! 
By the same artist, known under the names of Shouka, Matsuka and Kayoudou, I also share Juunengo No Jinsei Soudan (“Life Consultation After Ten Years”, 150 pages), Sisters Panic (uncensored!), Juujun X Yokujou ~ Furinaite Wa Jibun No Kyonyuu Seito, Das Parfum, Hanekawa BLACK and Hanekawa White.
