I mean, giving the option of booty babies would probably help in the 'how the hell does x character get spawned' if there's only males about.
...Unsure about delivery, though. Maybe it's an egg or has a protective shell, so you're effectively passing a bowling ball through the rump? *winces slightly*
Most of those options are things the player could mostly set in their ledger, but like, nothing wrong with that. Especially if it's something they gamer wants to see an effect of.
Frivolous is fine, but silly mechanics are also neat, especially if it helps tweak a build or something, possibly in ways other skills or feats do not. Maybe a mix of both?
--
The irresistible effect... may be more fun if it works both ways. Everything is more suggestible in your proximity, very much including yourself. Effectively relaxes requirements for lewding others or being lewded.
Increases the rate of advances, attention based by appearance, positive or negative.
Lore wise the player already had something akin to this going, but not crazy powerful.
...Perhaps it could be further empowered, to the point where it would behave much like Bibto suggests at later stages.
...Though I'm not a fan of body writing. Maybe leave that optional?
--
Semi related, but what about some sort of house / family mark on the body? Not limited to blood relations, the mark (essentially a small symbol or tattoo) that has a very minor boost to stats or ability, that grows in potency the more souls that choose to wear it. The location could vary, as does the size, but it could be a way to tie friends, lovers, and family together.
Maybe it resonates when others marked with this are nearby, letting you know they are close, (this could be useful in tracking down those that are kidnapped and such, mechanically) or perhaps it just aids in surviving some of the nastier magic that would outright kill normal beings, such as being in the environments that would normally cause the nose to start bleeding.
For a visual example, consider the manga / anime of Fairy Tale, that sort of vibe.
Or amusingly, maybe this manifests once you've reached x amount of favor with a given character, regardless of intent.
Perhaps an ability that is learned at later point, is an ability to embolden the bond or mark. With select few you may give them your blessing, further bolstering the marks effects.
--
This is probably more of a just a racial kit or perk, but no reason the others couldn't gain it from marks or enchantment- stretchiness. For Ratkin, small Farie and Goblins this is essential. No porn logic, no survival. Especially since there's all sorts of horse sized encounters (and more) out there. As to why it works, well, it's magic. Where there's a will, there's a magical way and all that.
Or to quote the great doge: If I sits, it fits.
Although this may just be better lampshaded and moving on. Most of the lewd art and proportions are quite unrealistic anyway.
--
Here's a fun one, though it's probably a bit too similar to come concepts I was planning to plug with the Monastery update stuff. Mana circuits.
You draw additional strength from the patterns on your body which draws from the spirts, elements, and magic in the land. This operates on the principal of bikini armor or anything else with high exposure, for it to work, essentially you are stronger the more of you is exposed to the world.
While useful, anything that has medium armor or higher, or conceals the body would nullify this effect. If needed for balancing, perhaps the body being covered in this way actually makes the PC feel uncomfortable or lethargic, leading to a stat penalty.
For extra fun and flavor, maybe these circuits can grow stronger the more primary elementals or spirits you bond with.
And by bond, of course I mean fuck.
Secret of Mana style, huzzah.
But in all seriousness, this could totally be a thing for a 'magic' based race that is Fey or Faerie, potentially. Magic or contact with the spirits is the same for them as needing light and air for most others, that sort of yarn.
--
