[Need Help] Can't Remember the Title Circle/Artist 2

[maihime2676]

okay i'm back again after long time and it's just another reading hentai doujinshi until suddenly i remember doujinshi that i cannot find it.

so here's the plot :

Spoiler: Hint

It's an NTR (from the girl point of view) where there's this girl that go out with boy (the boy confess to her if i'm not mistaken since it's not really that pointed out) and hanging out with her friend and that boy friend (the friends are not couple).
at one point they're having this study group for test but the boyfriend is arriving late because something, then the friend (girl) went to the toilet, shortly after that the friend (boy) go to toilet too, since the girl wondering why taking so long she check for them and found out they're having sex and peeking them.
after they done the friend (girl) passed out, and the friend (boy) know that the girl peeking them and take the chance to do it with her but unfortunately the boyfriend arrive and it was not happening.
then he blackmail her so they can have sex.

it was multi-work series that running for about 4 or 5 episode, with x-ray and nakadashi.
the art is not like modern art, it's more like old fashioned cartoon that doesn't have much details but decently erotic.

so please help me find about this masterpiece so i can be at peace. :D