Man, Bayonetta hits a lot of the right buttons for me.
That said, a lot of it does actually come down to her personality and how she's written. She's just comfortably confident in a way that makes it easy to like the character, which then enhances what if any sexual aspects may be involved because it's of a character you actually want to see, at least in my experience. Even sans any actual sexual attraction, the character strutting her stuff and being framed as actually owning it (obviously fictional charcters do not have true agency, but then why even discuss their motives and character at all?) makes her oddly cool, and I damn well wish I could have her kind of confidence to absolutely dominate a scene, whether with her body or wit.
Mind, I don't think the games are 100% perfect in delivering on this depiction of Bayonetta, and given the inherent subjectivity of sexual taste, can understand if people quite easily find it cringey. The pole dancing end sequence for 2 kinda had me going back and forth, for example, because while on the one hand it does seem like the sort of thing Bayonetta would do for kicks, it was also kinda shallow and doesn't really work with how her model - particularly the legs - is designed. And given its place in the ending sequence outright, it came off more blatantly as a designer's indulgence, vs the first one's dance number (though that too is an obvious indulgence).
