Aisareru Karada

Yui has a small body and has always wanted to have a big, muscular body. He enrolls in a gym with Tachibana as his instructor. He’s the guy he has been idolizing in some body-building poster. There is another story in this manga entitled Taberarechau. A bit incest, Yuu moved in with his relatives because his parents moved south for their jobs. A friend warned him about Hiromi (his cousin, I guess?) who seems to be going out with a guy.

Included oneshot: Taberarechau!
Yuu moved in with his relatives because his parents moved south for their jobs. A friend warned him about Hiromi who seems to be going out with a guy.
(Source: MangaUpdates)