Who the fck is u n what is happening im lost here 😵😵

He is his older half brother and I’m assuming he hates him in a way bc he kept annoying him. The younger brother who had the handcuffs on is a friend from uni of the main character. Also the hyung works for the guy who can’t taste sweet things I think. I can’t remember the names of the characters bc I haven’t read it in a while, but I hope you get what I just tried to say. I tried. I’m pretty sure he’s also the one who stole the money but idk yet :)