I think characteristics for friends are different for everyone, especially between someone your age and mine. For you I would think it's someone who you can have fun with and someone who will always talk with you when you need them. someone with similar interests and someone who will apologize after making mistakes and someone who will forgive their friends for making mistakes. and you probably need to like the same music as long as it's not beiber.
Yes. Purring is a definite must. Killing small rodents and birds is mandatory. Clawing up the furniture is not good.