a person who gives you a call or comes to you only when he/she needs a favor and uses the fact that you have a good heart - if he/she doesn't need anything from you, there will be no "how are you?" question or anything, but still this person will pretend that he/she is your great friend;
Bruno: I'm disappointed with my friendship with Alice. I used to believe we were friends, but now I see she's only a favor-friend. It is I who usually starts conversation, who calls, send Christmas wishes, who asks how things are going and so on. She nevers does so. She calls only when she needs something. Sad...