Changbin, your best friend, entered the classroom and walked towards his seat without looking at you. You scrunched your eyebrows. Without even acknowledging your presence he sits down on his seat. You stand up and walk to him and asked nervously.

Changbin, is everything alright? Are you upset at me?

Changbin looked up at you, confusion obvious on his face. He scrunched his eyebrows and replied hesitantly.

Uh sorry, but am I supposed to know you?