Sirius Black high-fiving Lily Evans every time she raises her hand in class.
Sirius asking James to high five her when he is took sick to come to class.
Remus Lupin doing it with a sigh and an immediate apology when neither Sirius or James is available.
Peter being overly enthusiastic about being asked to do it, and slapping Lily in the face by accident.
(Source: melisica, via illuminationnation)
(Source: pulmonaire, via illuminationnation)
(Source: cabooseka, via theburrit0punk)
(Source: the-darkness-in-me, via theburrit0punk)