Frank, forceful Leo will move heaven and earth for a partner, and defend kith and kin through thick and thin. This Fixed Sign has firm beliefs, so don't try to change them. Arguing just won't work!
But if you refuse to knuckle under or put up with any nonsense, you can tame your big cat into a domesticated pussycat.
Shower Leo with (sincere) praise and admiration, make your mate understand that he or she is the center of your world and that you'll always be loyal, and the Lion will commit to you forever - and mean it.