the author chose the age of 18/19 to get out of that problem on a technical level, even tho that age is still a teen with a teen mindset so really the principle of it is still the same.
idc if you want to read this or if you think its not weird at all, i just find it funny that whenever you have these types of stories where the literal adult knew/took care of/raised the younger guy when he was a child or teen, they always make the younger one the top for these reasons because they know its a weird situation.
Age gap is 12 years. Seme will like him first. Bit uke (gangster), doesn't like him that way. He does loves sejin but in familial love as in replacement for his dead sister.
Seju (uke gangster), will run away once, when he realized sejin feeling love. But then he come back to his house (sejin stays there), but seju drew a line. Like hard line. But it actually no use, sejin already knew all good things seju did for him, so his love will only grow.
No grooming. Seju pour out his affection because he thought sejin will leave him after he turn 20yo, but sejin wants to stay instead
Pls don’t turn this into another grooming trope