
I'm not into rape like stuff and don't read it often. This is more settle ig but i tried
Might not be ur taste
http://www.mangago.zone/read-manga/rojiura_pussycat/
http://www.mangago.zone/read-manga/chihira_kun_wa_maryoku_ga_tarinai/
http://www.mangago.zone/read-manga/our_house_love_trouble/
http://www.mangago.zone/read-manga/afurete_koborete_gaman_dekinai/
http://www.mangago.zone/read-manga/yagi_to_ookami_no_hatsujou_jijou/

not really realizing they're gay per se, but some kind of rape conditioning slash stockholm syndrome situation
http://www.mangago.zone/read-manga/nani_ka_ii_no_mitsuketa/
http://www.mangago.zone/read-manga/rojiura_pussycat/
if not these, i suggest going to the straight to gay tag... a good number of those started out woth some form of rape or like very dubious consent
i want some yaois that they are straight but when they get raped by a man he falls in love with him and becomes gay- PLEASE HELP IM GONNA CRY ┗( T﹏T )┛