Do you mean Stockholm syndrome?
Try “Hwang young’s misery”
Vivarium
It does match what ur looking for I think, check it out!
So glad you asked this! I've been waiting for someone to ask that kind of manga because I've been wanting to recommend Kansai Jin to Hukuman Satsujinki. I couldn't recommend it to just anyone because of the genre and theme.
Anyway, here's the link.
https://www.mangago.zone/read-manga/kansai_jin_to_hukuman_satsujinki/
'Two in six billion'-- read the TWs
ik im a weird shit but like does anyone knows a manwha or manga where like the victim got in love with his kidnapper or smth like the killing and stalking type of story