She's Gyoon's mom, not exactly the kindest character, but she doesn’t do any damage, don’t worry. It’s Gyoon's brother who sucks. He’s the reason why Yohan can’t hear — he’s a stalker and likes to hurt people close to Yohan to keep them away. Gyoon is the only one who stays ’cause he feels kinda responsible for the incident. Btw, he’ll hurt and kidnap Soohwa in one of my favorite parts. That delivery man is also part of it, so be aware.