I'm looking for a specific yaoi manga: the uke binds the seme's wrist and tries to "have his way" with him, but the seme can't get it up...at least at first, afterwards he gets in the mood. I remember they are in a bathroom (school) and the seme is good looking and the uke is plain looking. I think they end up together...

Pease help!

Is it chap 7-8 of Itoshii Akuma? 😕

YES!! That's it!

Thank you, thank you thank you! 😀

Are there any other mangas like this: where the seme isn't interested with the uke, maybe doe's feel turned on by him or something, but that changes later?

Yume Musubi Koi Musubi
Owaranai Fukou ni Tsuite no Hanashi

Also try the 'Persistent Uke' category tag?

Nice! I really liked those, especially the second one!

Are there any others?

You could also try the 'Nympho Uke' or 'Perverted Uke' with the previous tag I mentioned for more series.