kafferast
A person who’s so nice, they let you get away with stuff, but they’ll laugh when you mess up. They’re like a friend, but also a bully.
My brother is a kafferast. He let me use his video game, but he laughed when I lost to him.
She’s a kafferast. She let me copy her homework, but she laughed when I got caught.
He’s a kafferast. He let me eat his lunch, but he laughed when I spilled it on his desk.