does seoin even knows that his mom paid yeongwoon's dad money to get him away from seoin.....

I’m 1000% sure seoin is in the dark about everything….remember how he waited for yeongwoon before he left? He had no idea

I dont think thats what happened. There was an article on the table saying the dead brother had like immunity from doing school violence and that they faced little to no consequence. I think mc was bullied by dead brother, which was shown in his flashback and mother paid mcs family to shut up. She probably feels guilty for helping her son ruin mcs life thats why she ran after him.

OH THIS MAKES MORE SENSE.. i thought she paid yeongwoon's father to get YW away from seoin because the scene looked exactly like that