San Andreas: You gain strength ("muscle" in SA) by eating food and working out. Not only does it increase the damage you do in melee, it influences your respect and sex appeal stats as well. It's not so simple though, as having a muscle level too high will actually decrease your sex appeal once you hit Marcus Fenix/Abby Anderson levels of bulk. Do you lift for the respect and admiration of your homies or for women? Choices and Consequences.
Generic ****** RPGs: Gain reputation by picking the obvious suck-up dialogue choices. Changes an ending slide maybe. Yawn, boring.
San Andreas: Earn your gang's respect by capturing territory, spraying over rival tags, building muscle, having a lot of money, getting pussy, and wearing gang colors. Every rival gangbanger or drug dealer you pop earns you a small amount of respect. Higher levels allow you to bring more gang members with you, up to seven!
Generic ****** RPGs: Charisma blah blah blah you get it. Invest point, become more attractive or whatever.
San Andreas: CJ's sex appeal stat is more than a number; it's determined by many different factors. Your physique, hairstyle, tattoos, quality of clothing, and experience with women play a role here. You're probably overwhelmed because you've never seen anything more advanced than a Belt of +2 Pussygetting, but there's more. San Andreas actually takes into account the vehicle you're driving and the condition it's in. Obese with a yee yee *** haircut? Compensate with a sports car - you'll benefit from it as long as you're close enough for women to see it belongs to you.
I'm only half-joking. RPGs could learn a lot from San Andreas.

