http://www.mangago.zone/read-manga/konbini_kun/ (seme grinds on him and then they do it lol)
http://www.mangago.zone/read-manga/k_sensei_no_yajuu_na_aijou/ (ch 3 sexy grinding in the bathroom)
These might also have it:
http://www.mangago.zone/read-manga/himegoto_asobi/
http://www.mangago.zone/read-manga/elektel_delusion/
http://www.mangago.zone/read-manga/benriya_san/ (has a bit of grinding)
http://www.mangago.zone/read-manga/kyoushi_mo_iroiro_aruwakede/
Any yaoi manga where the seme grinds on the uke or f**k between his thighs? Thank you