Comment by corpse_bride on Backlight - Chapter 32

@corpse_bride What do you mean? Seo-In wasn't the kid who beat up Yeongwoon, that was his brother. ALTHOUGH you could convince me that "Seo-In" is actually the brother and it's Seo-In who's dead and the brother went insane from his death and decided to emulate everything about Seo-In right down to his obsession with Yeongwoon.

@OpalEyes the one who beat yeonwoon was the brother. He had light brown hair. seo in back then had black hair. The moother had to have know thats why she is having the breakdown.