Meet cupid! He's the darling angel that's going to make you fall in love forever with your one true love!
If someone does something nice for you, then you should go out of your way to do something back. Reciprocity is the name of the relationship game and always will be. If you want to keep in touch with someone on a personal level, you need to be willing to do a favor for them every once in a while. Because before long, you'll need some help, and you might not have anyone to turn to.