Yaoi with the seme shorter than the uke? I only know of/remember Otona Keikenchi and Natsu...

http://www.mangago.me/read-manga/melancholic_mellow_mellow/

http://www.mangago.me/read-manga/koitomo_/
though you have to read its first parts in Katekyo.

Urahara to Dilemma by Naono Bohra! (⌒▽⌒)

Thanks everyone!

nirameba koi

http://www.mangago.me/read-manga/koitomo_/

http://www.mangago.me/tag/bigger%20uke/?page=1