Rizz is slang for when someone has a lot of charisma, in other words: Rizz, if they have a lot of rizz they have W Rizz, or on the other hand if they don't have a lot of rizz they have L Rizz.
If someone has an immense amount of rizz they are considered a rizzler
"Hey have you heard about Kai Cenat?"
"Yeah, I heard he is a Rizzler"