So I read this manga a year or two back, that was some smut seinen I think. Forgot about it cause, at the time, scanlation wasn't finished, and I never wrote the name down. Though I'm pretty sure the series itself was at least finished with less than 10 volumes. I could be wrong about the less than 10 volumes part, but I doubt it (scanlation was around 20-30 chapters, and it seemed like it was coming to an end soon).
The story started off with our protag (who remained somewhat of a wimp throughout). His house burned down when he was young, or his parents died, or both, so of course he went to live with his childhood friend. And I know there was something going on between them, possibly a promise of marriage somewhere. But the friend was obsessed with him. Claimed him as her own. Touched herself rather erotically to thoughts of him, once right in front of him. Even went yandere and used a knife to write her name into his chest when she found him boning another chick from school.
There was, as I mentioned at the very beginning, a sex friends club that came into play maybe a couple volumes in, which his main lover had a past with one of the other girls in that club. I'm also pretty sure it was during one of those club trips the childhood friend finally went full yandere and wrote the name with the knife.
The last chapter I can remember reading (or last two) was about our protag, still kinda a wimp, ended up boning one of the SF club members after the group (I think) died, because she was having some problems. And then he was forced to bone the megane-chan bookworm in an elevator. All while trying to hide these things from his main lover, which he was either living with or also married to.
And that's pretty much all I remember. Does this sound familiar to anyone?
