Both words have long been subverted to mean the opposite. Together they have a double opposite-negative power to express that something is extra cool and exciting.
"You wanna go see Bowie play live?"
"Yeah, wicked and bad!"
"Wanna go out for dinner on Tuesday?"
"Yeah, I'm free. Wicked and bad - see you then."
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.