Imaginos body is the answer. She can pop a vagina, an anus and even a dick whenever she wants. The anus is probably already there, too. she clearly have intestine when Nova regenerate her in last Order Vol 1.
And she pee, too, if you consider the little omake cannon.
hmm, sweet sweet gally's pee.>>11355177
Fuck yeah, that scene has such a great doujinshi potential.
"and now, for having hust me, you'll have to..."
"suck my cock!"