So yeah, I think Rimuru sums things up well here. There’s a lot of sex that can be done without the use of genitals, and not just with male partners like we see here. The last time I drew Rimuru he was using his mouth to please a lady, so he’s got those options. Of course he could probably use his slime form in some interesting ways, too, but I’ve been wanting to draw Rimuru taking dick for ages (it just never seems to come together into a finished pic). Another option Rimuru doesn’t mention here that exists within the Studio setting is growing a dick the same way Frieza does, but I didn’t want to bother with getting into that here since it’s just some obscure NHS lore that would’ve been too distracting.