I'm not sure how to craft an effective search for this question, and I don't recall it being addressed within the game, but...
Before logging on, MC mentions a couple of times about taking a piss before playing so he doesn't wake up to an accident. Since the game experience is supposed to be very realistic from a mental response to in-game physical inputs, shouldn't the MC be waking up as though he had a wet dream after some of his in-Eternum encounters, or does the game give the mental satisfaction while suppressing the "real world" consequence? I know other physical activities are suppressed, so maybe that's the case. If no physical suppression, I'd hope they design the game suit with "receptacles"...