What would a real friend do? You have lost your bus fare home, and your friend has only got enough money for one fare. Leave you to walk alone. Walk with you. Give you their bus fare and walk in your place.
What would a real friend do? You and your best friend both fancy the same person. Both go for it – see who they like most. Both back off and put friendship first. Back out and give you a clear run.
What would a real friend do? Your friend has been picked ahead of you in a school sports team, but you are the first reserve. Avoid mentioning it. Try to injure someone to get you onto the team. Fake an injury so that you can take their place.