Plot: The first volume is all over the place and ridiculously fast paced, but after that, the volumes fix their pace and are quite enjoyable. There is a plot but the manga is mostly just sex & foreplay.
Characters: Sarasa was my least favourite character and he really needed to be in a mental institution or at least get a therapist. He was immature and selfish, but the audience is expected to pity him due to his backstory. Despite that though, he was a (relatively) complicated character which is rare in manga nowadays.
Kazunari however, is protective and kind but his character needed a backstory which
was hinted at but never truly delivered.
Sex scenes: Absolutely gorgeous and there were plenty of them. Each one was unique but never dropped in quality.
Conclusion: Try reading through to the middle of the second volume, if you want to continue, it's highly worth your time.