I don't think Byul's feelings are rushed. We got hints earlier that he was interested in him, he followed him around, asked people about him which showed signs of typical teen crush. Maybe it's not yet developed to be mature, romantic love, because it takes time and a lot of work, but he could catch feelings this quick. I think for the rest of the story, author will explore path that it takes teenage love to grow into adult love, or how feeling doesn't always fix everything ╮(￣▽￣)╭
I hope this will only be a ground for therapy arc, because what the actual fuck happened to Inseo
Yo, a remainder for y'all:
If you hate a character, the author did a good job.
But remember it's a scripted story, nothing is black or white and people can be great to ones and horrible to others. Don't let misogyny and patriarch teaching blind your reason
Facts