Spun my randomizer wheel and got Outertale Gaster, so that’s who’s getting spicy headcanons next! Everything is under the cut vvv
Asterisk is very by-the-book when it comes to relationships and this includes physical intimacy. He waits until after several proper dates before even asking for a kiss, let alone anything else. Every move is intentional and with full respect for the person he’s with interested in. This means that he moves very slowly, so if he love interest even want to actually get him in bed, they’ll want to push him a little bit.
He’s also completely unable to talk about anything sexual with anyone but an established partner or he’d be blushing up a storm. Asterisk considers any information of that nature to be completely private and would be absolutely mortified if anyone brought it up.
He’d also be equally as mortified (if not more so) if anyone found out he reads dirty sci-fi novels. Which he swears he didn’t mean to read! Initially he simply picked up a book Alphys left in the lab and intended to just skim through it, until he got a few chapters in and it was obvious what the book was really about. But he couldn’t stop reading it. Truth be told, part of the reason he likes those books so much is precisely because it feels so scandalous to be reading them. Not that he’d ever actually want anyone to find out. He’d rather crawl back into the Void.
Once he has an established partner, he much prefers their company over his books, although he’ll likely still try to sneak a few chapters here and there without his partner knowing (it’s still too embarrassing to mention). Asterisk may also try to suggest things from said books to bring into the bedroom, although he’ll try to be as inconspicuous about it as possible. That’s really only if he’s feeling particularly daring though.
On a normal day, he’s just slow and attentive, even exploratory, and often prefers to keep most of his own clothes on, especially in the earlier stages of a relationship. The two things he’s not shy about is summoning extra hands or using his magic to distort gravity. (That can happen on accident though, if he’s really riled up.)