Kiwi.

-Demon of lustful hell
-My suha
-Trap city
-Hold me tight
-Paid
-Shame application
-Stigma (There are multiple. The cover looks like a guy smoking, with another guy in the back of him. Black and gray color).

Therapy game (and its prequel)

http://www.mangago.me/read-manga/itoshi_no_mitsuyoku_circus/
http://www.mangago.me/read-manga/osuppai_oshiri_bl_anthology/
http://www.mangago.me/read-manga/ai_wa_kane_nari/
http://www.mangago.me/read-manga/uta_no_prince_sama_dj_ookami_shounen/
http://www.mangago.me/read-manga/gomi_to_kuzu_dangan_ronpa_dj/
http://www.mangago.me/read-manga/munetaka_sama_no_dame_maid/

http://www.mangago.me/home/mangalist/127166/?filter=&page=1