Sex and sexuality isn't one size fits all in real life. But in Fallout 2, there's a literal formula that determines how good your character is at boning.
A quest in Fallout 2's New Reno requires you to become a porn star, which meant that knowing how good your player character was at sex was relevant to the plot. To this end, then-Black Isle devs Chris Avellone and Tom French developed an equation to suss it out.
So how did Avellone and French determine what makes your player character good at sex? Well, it was inspired in part by personal experience. In a chat with Chris Bratt from Eurogamer, French said, "This girl that I was dating was way into this guy that was way better looking than me, so I was like, you know what? Charisma plays a much bigger part in this." The equation weights four attributes — Charisma, Agility, Endurance and Strength — multiplies them by different variables, divides them by 100 and then adds any modifiers from traits like Sex Appeal, giving you an objective number that relates your character's sexual ability. For more details on how the equation was developed and how it works, check out Bratt's video below.
French also told Bratt that if he were to rewrite the formula today, he'd make a few changes. In particular, he said that he'd try to weigh your player character's Charisma stat against their potential sex partner, instead of judging it on your Charisma alone.
If your Fallout 2 character was especially skilled in the art of making love, they'd gain the reputation "Gigolo", which Bratt says the team now regrets. According to Bratt, they told him that a descriptor with a value judgement attached limits roleplay, akin to calling someone a liar as opposed to a trickster. I'm not sure what a more neutral term would be, however. "Good Sex Haver?"