Being completely honest, while I like that Yeonho was able to convince him (the young master) to essentially give them and their relationship space in the guise of him realizing his full potential and coming into his own as an adult, I'm not fully satisfied.
To begin with, I don't like the son all that much. I think he's emotionally manipulative and borderline abusive even if he doesn't mean to be, and he's just another side to the coin that was his father.
Time and again we've seen him behave erratically and be quite possessive over Yeonho, obviously with the father around, but also people with less evil motivations — like the detective just trying to do his job, albeit invasive...but that's his job.
He pressures Yeonho into being with him, first as a method of getting away from his dad, then again as a way to protect him from the authorities, and then AGAIN by allowing Yeonho to believe he might kill himself (c.51) if they can't be together.
It is literally emotional blackmailing.
We've seen that when Y keeps trying to drop their relationship, or just say that they need time apart, then he quickly switches from pushing to pulling away REAL hard. Instead of reassuring Y that he understands and is willing to give him the space he needs to just think and breathe, and that he'll be there when he's ready to talk, he instead stops talking all together, makes it clear that he'll leave and there is no guarantee he'll come back (though we as the readers know there's no chance of that). It's all very hot and cold. He lets Y be on the verge of another breakdown before he's immediately there again, pushing yet again for his own needs/wants until Y ultimately gives in. Instead of receiving the time and space he'd wanted, and I think REALLY NEEDS, Y was forced to compromise.
Take into consideration that Y has lived the majority of his life under the abuse and control of a figure with authority over him, and is living with trauma, and now he's put in that exact same position, where again it's next to impossible for him to say no, and he's had zero time to process that trauma and everything it entails, and this feels like a bad relationship to me.
If he'd given Y some time alone, some time to meet other people, make friends (because you'll notice he has zero friends or family), meet potential suitors — if he'd given him a chance to really get into a healthy mental space to make a decision on his own behalf, I'd like it more... but that's not what happened.
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