As a general rule of thumb, if the game is Japanese, and was/is available on consoles, it won't have any actual nudity, their ratings boards won't allow it. Actual nudity in their games will automatically push the rating into their AO equivalent, so you'll maybe only ever encounter it in PC-only titles, and even then, it's VERY uncommon outside of the porn (or close to it) type of games. I'd imagine many are probably surprised by this, as there are a ton og Japanese games that are very risqué, characters in next to no clothing, huge boobs bouncing all over the place, characters moaning and being lewd, but you'll notice none of them ever actually cross the nudity barrier, and those that do will have some sort of censorship (character faces and beams of light in Senran Kagura for example).

Ratings in the West are different though, and will allow for nudity without pushing the rating up to an AO, so you could expect it from non-Japanese games.

*** Quoted from a steam user.