[... Okay, it was her fault for being vague, there.]

I mean, that's good! But you're allowed to not be in the mood, too. And if you're not up for it I just want to know you won't get upset if I, y'know, masturbate or there's someone else.

[Her Glaceon is not an on-demand sex slave, after all, and after a certain point his interest in sex might even flag. That's all she's saying.]