"Portrait Study" by fantasio is used with permission
Characters have their own sexuality, whether or not they've actually had sexual intercourse. They arrive at the gaming table with their own predispositions, awareness, and expectations. You might not be aware of these things at first, but there's no rush to cover all of the bases at once. Over time such details might come out during play, or you might develop them on purpose.
Sexual History: If your character starts play as a full-fledged adult, try to imagine what their love life has been like. Have they been spurned regularly, or are they used to admiration? Have they been burned by love, or by one lover in particular? Are they restrained with their emotions? Or are they trying to flee a match that was made against their will? These details can reveal more than attitudes – they can be the start of adventures.
Morality: Since games often rely on stereotypes, you can refer to the different groups your character belongs to and see how they've affected his sexuality. An easy place to start can be alignment. How does your character's moral outlook govern their romantic conduct? You can fall back on the expectations for your alignment and go with the marriage-bound paladin. Or you can play with those assumptions, and create a chaotic evil character who is gentle with lovers – so his victims will feel guilty later about the pleasure they shouldn't have felt. But keep in mind that anyone can err, and alignment alone doesn't dictate a character's relationships.
Race: A character's race can be a more complicated matter, though you can base your ideas on the larger stereotypes at work in your game. If dwarves are stodgy and prudent overall, then you might declare that they are usually straight and monogamous, marrying one dwarf for life. Instead of making such general statements about the multitude of different races, I suggest you weigh the following aspects for whatever race you want to develop:
Environment & History: A race that is traditionally tied to a particular environment will be affected by it, if only through customs. Dwarves who are used to spending months in silent underrealms could be masters at keeping quiet during sex, and might hold moans of pleasure to be taboo. Elves might have sex whether people are watching or not, since there is nothing shameful about the act and they have seen it all already. Likewise, history can take a toll on people. If half-orcs are shunned and hunted, they might mate with any other half-orcs they meet so they can experience some interludes of pleasure. If halfling populations have dropped terribly because of famine and war, they might look down on purely recreational sex for a while and offer incentives to new parents. Races that are spread across different regions will probably break some racial stereotypes in favor of local events.
Alignment: If an alignment is associated with a race, it will probably impact sexual practices. You can imagine how alignment affects marriage expectations and other romantic aspects. You might also want to ponder how your character's alignment has come into contact with the alignment of their race. For example, in one game I ran, Grabthroat Shinkicker was a dwarf who left the mines young and fell in love with the sea, of all things. He always stood out at home because he didn't like to follow ironclad rules, and his chaotic good alignment matched his freewheeling sexuality. Not only did he have a lover in every port, but he liked to experiment with different races and was dead set against getting married. Many other dwarves thought he'd spent too much time with humans, or pitied him as a lonely man with no understanding of the finer things in life. Grabthroat got pretty sick of those attitudes and generally preferred other races to his own until he met a dwarven cleric who saw him for the good dwarf he was.
Lifespan: It's difficult enough for humans to create lasting bonds, and they're only given a maximum of 70 + 2d20 years to live. It's quite another thing to face the prospect of lifelong commitment and fidelity when you're an elf; you reach adulthood at 110, but can live up to 350 + 4d% years in total. That's a long time to get to know someone more than you thought you could. That's a long time to argue and separate and be tempted – as well as to grow bored and experiment. While some longer-lived races might still expect exclusivity from their members, others will be open to serial monogamy, polyamory, temporary marriage, or other arrangements. And while some races will have their taboos, others will accept a wide variety of sexual practices – if only to pass the time more enjoyably.
Relations with Other Races: If races are known to be steadfast allies, they might also be regular lovers. Half-elves stand as proof of the fascination that flares up between humans and elves. Gnomes and halflings often find their lots thrown in together, and since they're the same size in a world of larger people, they can easily pair up for fun. Whether or not children can result will largely depend on their type (see the Pregnancy section for more details). You might also want to assess how half-breeds are received by their parent races.
Sexual Orientation: Regardless of whether orientation is a matter of biology or choice or something in between, it is a part of a character's sexuality that can be good to know – but difficult to bring up in-game. Since every group is different, it's best to approach your group before adding the element to the mix. On one hand, many of us want to encourage a sense of openness and mutual respect that isn't affected by sexual orientation. On the other hand, some people don't want that, or don't want to deal with such a hot-button issue during their weekly escape. If a compromise can be reached, the group might be better for it. But if there is a major negative reaction and people aren't willing to compromise, then it will probably be more enjoyable for everyone if you find a group that is more comfortable with sexual orientation before proceeding.
In any event, it can be helpful to specify the line between yourself and your character. Just because you play a character who is gay doesn't mean that you are, and vice versa. It can also be easier to introduce sexual orientation into a game through NPCs, since they are at a greater distance. But if your group is happy to add orientation, then you might want to play with expectations. A good example of this is the character of Lafayette on the television show True Blood. Though he might wear makeup and loud clothing – and makes no bones about being gay, even in a small Southern town – his muscles and confrontational nature provide an effective contrast to his feminine touches.
It can be good to think about how your character's sexuality was received, and if you're a Dungeon Master, you might want to think about how different places handle orientation. Some societies might not care at all; if you're a citizen in good standing, who cares who you sleep with? A few cultures might not have much to say so long as members produce children during their lifetime. Other societies might punish one orientation harshly, or more harshly than others. The goal should not be to torment a character for their player's choice or to ridicule one orientation, but to open up new adventures for the group. Maybe the PCs can make a difference in local laws and work to change cruel customs.
Consider the intersection of race and sexual orientation, as well. Do dwarves refuse to acknowledge gay children? Or do elves expect other elves to be bisexual, to the point that being gay or straight is ridiculed? Is it taboo to ask a halfling their preference unless you're looking to find out first-hand?
But whatever you do, keep an eye on how orientation is portrayed. Sometimes we fall into stereotypes without meaning to, and you should be building a character – not a caricature. If someone at the table is making one too many jokes or acting in a mean spirit, anyone at the table should feel free to say they're not happy with it. If you notice you are relying too much on cookie-cutter models of gays or heterosexuals, take a bit of time to adjust your approach. If you feel like someone is taking it too far, talk to the group before or after the session. Don't just let it pass, because you might not be the only one who's disturbed by it.
Virginity & Chastity: In real life, many societies value female virginity and chastity well above that of males, but fantasy cities don't necessarily have to follow suit. Even our own world isn't consistent about such attitudes. For example, virginity beyond a certain age is often greeted with worry or suspicion (at least where I'm from). A former neighbor of mine was a lovely 28 year old woman, but when people found out she was still a virgin, many automatically wanted to know what was wrong with her. That she was visibly beautiful and healthy only seemed to deepen their suspicions.
But there are many ways that these aspects could be different for your character, in your game. If a culture is sexually open and encouraging, inexperience of sexually mature people might be deemed a bad thing, a point of selfishness or willful ignorance. Or, if you lose your virginity too soon, elders might “fix” it with magical spells that heal the body and erase the experience from the mind. Chastity could be voluntary, or commanded by a character's god (and in some settings, the gods can have very direct influence). On the other hand, it might be enforced by spells or magic items, or completely and totally valueless. Reliable birth control and spells that detect the parents of a given child can affect attitudes about these things, which in turn will affect customs.
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