A 'special friend' who you enjoy certain 'benefits'. Though not to be confused with the term 'friends with benefits' or 'fuck buddies'. A non-committal relationship between two people, though friends, partaking in dates, have sex yet you don't have to make it 'facebook official' and, in principle, you can hook up with other people.
Isn't Drake dating Niki Minaj? Nah, they're just magic friends
A magic friend is a friend you are so close to, you can be honest and open about everything, share your ultimate famtasies with, and tell your innermost secrets to, someone you probably would fuck if you could but can't for whatever reason.
Philip is great, I tell him EVERYTHING!! He is my magic friend!!