let's look at the future. is the mc going to do "that thing" with Rushka? because if not, and there are various stupid plots that keep him from doing "that". then, welcome to the clichéd isekai story where the main character will be a virgin forever ... hihihi
if even there is something that keeps the mc from doing "that", then make it as sensible as possible. Like Ainz's undead race, of course he wouldn't be able to do "that" with albedo, and it was highly accepted by readers because it made sense and didn't look like a "stupid plot".