Dubcon

Veeery possesive rich boy is using hos "toy" (a boy sold to him as a kid to paly with) as a sex toy. The toy is very reluctant and does not like having sex, but is constantly used anyway. Flashbacks to when they were kids and this relationship started.

Teenage boy's mom dies and mom's boyfriend gets a little obsessed with the boy. Great build up without being too long. "Uncle" (seme) is very caring and kind. Uke is very deadpan and can't say no to seme who starts jerking off uke and eventually fucks him. Doesn't want uke to be away from home outside of school. Takes uke to a doctor that puts a tattoo on uke's belly to symbolize that uke belongs to uncle (who also compares this to castrating a male cat, so that it won't run away from home).