The sex does feel quite distinctly forced on the PC at several points, and it's not good, really.
The start, while I understand that they're setting something up, is very off-putting, in the way it functionally asks you to define who or what you want to sleep with, as though that's a thing that will be true for everyone - the option to say "many different people of many different types", or the option to say "No-one, thanks", or, if you're a bard, the option to say "Myself, really..." (mostly joking there, sorry), would really help a lot. Also it seems odd that the bug presumably delves your mind to look purely and only for physical attraction features, because it wants to win you over - but makes no changes or alterations to how it tries to interact with you, or the sorts of things you like or don't - if it were a smart bug, it would look at what we like, and how we like to be treated, and the kinds of things we go for, and psychical appearance would be only one aspect of that... It's almost funny that it puts so much effort into trying to find the 'ideal visual appearance to entice with', and then, for a large majority of people, completely fails at the first hurdle of social interaction in every other way.
You are right, though; I'd absolutely support paths of dialogue in romance settings that let you decline actual sex, and focus on the intimacy of the moment in other ways instead, without cutting you out of or negatively impacting the romance overall, if that's what your character wants.
