I don't think Bayonetta likes to sit around doing nothing for long, so we'd probably end up practising our Angel killing skills, if we're not already surrounded by them.
She also seems like she's probably very gifted on several musical instruments (piano, guitar and the like) and very educated, so I imagine she would be kind enough to teach me things. And how to speak the Ancient Umbran language.
Also, sweaty, exhausting lesbian sex could be on the cards, but we'd see how the evening went.