Uke and seme are already dating, uke is insecure in their relationship and kidnaps seme but seme doesnt mind because hes been like holding back his sadistic nature?
sounds like this one? i only read the novel so idk
https://www.mangago.me/read-manga/please_confine_me/
This author really loves some ass eating. Not that im complaining but holy shit its like nearly everytime they fuck