Want Sex Creep Friend To Turn My Respectable Sister Into A Slut

so ive known this guy since secondary school since i was 16 and have continued speaking into our adult years. one thing he was infamous for was how horny he always was in school. he either got lucky with certain girls or they turned him away creeped out and at times i kicked off at him over smacking girls bums and the sort.
one thing he seemed to always to love was my older sister, shes eight years older than us and was always a mature respectable and really nice woman but she was hot according to loads of people. she had shoulder length brown hair and was a pawg with large boobs as well. he always talked about her lewdly and tried flirting with her which i didnt like at first and she was often snobby when rejecting his advances but at times laughing at his attempts.
but at the back of my mind i really want him to succeed in taking her to his house and ravishing her ass to the point she changes entirely and becomes a huge booty slut. i mostly want nerds or even black guys to do it and cum all over huge ass