He doesn't want him to have anyone else to go to. I suspect he is actually behind Minimart's dad's death.
He doesn't have a resident registration number because his family never officially registered his birth. Without it, he can't access government services, enroll in school, get a job, or sign up for things like health insurance or phone plans. That's why he chose the Red Mansion, going to a real hospital would not only be more expensive, but it could also get him into serious trouble for not being registered as a citizen.
Yeah, Cheongrim being controlling is more like it. He could even hire a private nurse to look after dad instead of hospital (since he is so smitten, and caves into minimart's whims sometimes). But then he would have to compete for attention which, of course, he would never tolerate.
Exactly. Minimart loving anyone but him, thinking about anyone except him, wanting to see anyone but him... It's not something Cheongrim is going to allow.
Couldn't Cheongrim put minimart's father into a real hospital?! He should know red mansion people are no good.