This kind of fits the description:
http://www.mangago.me/read-manga/you_re_my_princess/uu/you_re_my_princess-chapter-4/27/
I remember one manga too, but i forgot if the one who crossdress is the seme? Bc the one who crossdress was bigger than the other one. I just cant really remember if he's the one who tops.
The crossdresser has red hair, the other one is really cute. There was this scene where the crossdresser's friend saw him crossdressing and thought that he was really a girl and kinda like fall for him. But then he saw the "girl" with the crossdresser's boyfriend (the "uke") and thought that he (the "uke") was cheating on his friend.
http://www.mangago.me/read-manga/nise_x_koi_boyfriend/
sound like this one
Yep, thats the one
this one's hawt BUT is that all?
so I'm looking for a manga etc. to read where the SEME that crossdress, or while he fucks his uke HAHAHAHA
TENCHUU(づ￣ ³￣)づ