Hey :) This one.
Hii :) Its from 3x13 , 26:04 ^^
plot twist: everyone dies at the end of 3B and season 4 is gonna be named Teen Ghost
"But Derek I don’t how to be the Ghost Alpha"
"I’m 5 pounds of ectoplasm, sarcasm is my only defence."
"Don’t be such a sourghost."
and Derek can be reunited with his family at last