Rule of Puberty
The rule saying that if you date an ugly/not so attractive girl before the rest of puberty hits, she will be hotter later on and you will still be dating her, resulting in your success and the envy of your friends. Has a 9/10 success rate. Can also be applied to dudes.
Doug: "Ew man why is Johnny dating Jill, she isn't even hot"
Jim: "Rule of puberty, dude"
*1-2 years later*
Doug: "I would totally bone Jill now, too bad she's still dating Johnny"
Jim: "Told you man"
Jim: "Rule of puberty, dude"
*1-2 years later*
Doug: "I would totally bone Jill now, too bad she's still dating Johnny"
Jim: "Told you man"