Yeah, it's a fucked up relationship with a yandere seme. Get over it y'all.

There's good ways to write a yandere and theres bad ways to write a yandere and this was bad

Well it's an abuser with childhood trauma and abandonment issues. Making the person you love a cripple so that they won't leave you is actually more common irl (among mentally ill people) than you think.
He wants his love/victim to stay close to him, to need him, so he created a scenario where this fantasy is brought to life. It's a horror concept that's not meant to be romanticised. At the end of the day the victim does end up needing him and due to the pleasure that comes with physical contact he also starts wanting him.
It's a weird and fucked up co-dependence where both parties make the other worse. You can't exactly call it romance, but one can find it hot as a fantasy.

For a media that tries to play it off as a drama, your point about it using obsessive 'abuser' with terrible childhood as a horror concept falls apart. Also this is a moderate story that can't implement tropes that it want to play around well, I don't think we should just 'get over it' when the author doesn't really try their best on their writing.