A really really cool person, who is mature and always plays hard to get. They are usually known as the hottest kid in school or most popular. Old Rat's are commonly known as the "cool kid on the block" and when you see one most people bow down on their knees and say "cat sucks on rat".

Internet persona(s) who happens to follow you and you happen to follow them back and maintain communication with and have a mutual liking for eachother whether it be friendship wise, etc. (Mutuals if more than one mutual)