Inverted nipples uke x muscles maniac seme:
Track and field club member uke is under constant courtship attack by photography club member seme who wants to take uke's muscular photographs. Upon discuss uke's problems he offer to help him cure it, in exchange uke will consider modelling for seme.
This manga reminds me of:
http://www.mangago.me/read-manga/seishun_kinema/
Go Houbi Chikubi