Responses
DANG THAT WOULD MAKE SENSE
Someone could've killed Hee-seo's mom to get revenge for whoever was pushed off and that's why Taekyung felt guilty and sponsored Hee-seo, because he should've been the one to die if he was the actual one to kill that person. And that's why he's trying to figure out who's Hee-seo's mom's murderer.
I actually think you're spot on but we'll have to wait and see.
Taekyung. Killed the guy while trying to defend MCs mom I think and pushed him off that cliff. And she buried him and was keeping it secrete to protect him.
That’s my theory.