This was a bit too messed up for my taste to be honest.
First chapter:
The senpai is a total player. Just because the kouhai doesn't let him f*** him, senpai decides to have sex in his bed with some woman. Nice. I know they aren't in a relationship so technically he isn't cheating, but he's still being a total dick. Firstly, he knows that the kouhai clearly still loves him (god knows why). And of course secondly, it isn't even his own bed. He did it on purpose, and that is just such a cruel thing to do. Personally, I'd never forgive someone if they did that to me, but I guess I've just got higher standards. The one thing I sort of liked about this story though, is that I do like seke couples, but unfortunately that whole scene was rushed so I couldn't even fully enjoy it.
Second chapter:
One guy has sex with his mum. Granted, he didn't know that at the time, but he still did it out of "revenge". Weird story. I do have to say though that I do like some incest plots, but never parent x child. Brother x brother ones are fine, especially if they've been estranged. Uncle x nephew ones are okay too. And I love step-brother couples (because obviously there's no blood ties, but it's still got the whole "forbidden love" vibe. Very hot in my opinion). But parent x child is just so sickening for so many reasons, so I really didn't like this one. Also, I know it may seem stupid, but I just don't like seeing heterosexual smut scenes in BL. If I wanted that kind of thing I'd read some josei or even hentai. When I read BL, that's all I want, just men on men.
Third chapter: It was okay. The relationship seemed quite nice, definitely the healthiest out of all the other couples in this manga. But it really wasn't groundbreaking or anything. Plus I don't really get mahjong so that whole plot kinda went over my head.
Fourth chapter:
Seme seems to have no romantic feelings for the uke. Even when he sees him kissing another guy he just walks off. Then he sees them together a second time, and suddenly he gets jealous. Wth? Why the sudden change from not caring to suddenly being all possessive? His confession is totally out of the blue as well. Such a shallow guy.
Extra chapter: I have to admit, I did quite like this one! Mainly because the senpai gets his comeuppance (kind of) lol.
Anyway, overall I wasn't impressed by this. The majority of the characters are all shallow and superficial, and none of them show any emotional growth either. The art is okay, but unfortunately the sex scenes are so short that they can't even be considered hot. Which is such a shame, as I was hoping for more seke scenes.