I've played NUDE...on OG Xbox. You get a robot girl (somehow, I forget), staying in your apartment with you, and you have to teach her stuff, like the names of things around the house.....by speaking Japanese to her!
It used the Xbox Live mic. There's a FAQ on Gamefaqs with the Japanese words in it, so you get to learn a bunch of Japanese words in the process! I'll never forget hana/hanabi (plant and flower, or maybe the other way around).
I never finished it and it wasn't exactly suggestive that there might be saucyness (being xbox and all!) but I remember it being really fun and the girl being cute. I wonder if anyone has it running on emulator?
Reminded me of Seaman, the Dreamcast game where you talk with the DC mic, to a fish with the face of a Japanese man, in a game narrated by Leonard Nimoy!
Life is crazy.
Edit: I found the wiki article, just now:
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and the trailer:
and some game stuff: