http://www.mangago.me/read-manga/only_you_moegi_yuu/ And there's a small continuation calls "Only One"
Katekyo has some of this in it...doesn't get real kinky but a teeny bit. Its mostly just cute teasing that can get a bit mean and the uke is just super patient.
http://www.mangago.me/read-manga/scandalous_seiryo_university/ not real kinky although there's some roleplay...its mostly just the seme is twisted as all get out but the uke is willing to overlook. Its funny and cute.
http://www.mangago.me/read-manga/the_4th_guard/ uke is pretty devoted to the seme, and the seme clearly adores him he just.. and I quote "loves to bully."
http://www.mangago.me/read-manga/karamete_de_kudoite/ seme is sex crazed. It doesn't go over real well at first though lol.
http://www.mangago.me/read-manga/mankai_darling/ established relationship. The uke tolerates the semes meanness and bullying. And groping, lots of groping.
http://www.mangago.me/read-manga/kawaisa_amatte_nanika_ga_hyakubai/ sadistic seme.
http://www.mangago.me/read-manga/aitsu_no_daihonmei/ shounen ai but its hilarious and cute. "seme" has a sadistic personality he hides from anyone but the uke.
http://www.mangago.me/read-manga/kare_otoko_ni_izumi_o/
http://www.mangago.me/read-manga/yume_no_you_na_hanashi/ this is exactly what you meant. Seme is pretty kinky, uke is just in love
http://www.mangago.me/read-manga/risou_no_koibito/
Or this.. more like the uke is the one that initially more into bdsm but then (i think) the seme somehow started to enjoying his "S" role
http://www.mangago.me/read-manga/yoru_wa_tomodachi/
In the mood for "sadistic or kinky seme with a uke who puts up with it all because he loves the seme" plot. Thanks for the help!