A slumberover is restricted to 2 people. This is not to be confused with a "slumberparty" which involves 3 people or more.
Also slumberover is not to be confused with a sleepover. Sleepovers are not associated with fun. For instance, a person might sleepover alone at a hotel. That's no fun.
"Let's stay up late and gossip about people."
"You mean like a slumberparty?"
"No, stupid. Parties require 3 or more people. Since its just us two its gonna be a slumberover."
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"