Castiel & Mazikeen
"Well. I can't make any promises, Mazikeen... but I will try my hardest not to end up being your ex." That implied that he was willing to enter a relationship with the demon, which was something he wasn't opposed to doing. "But I was thinking about something more along the lines of fun... along the sexual nature?" he suggested.
If she turned him down, that was fine. He wouldn't be offended, truly.
"Or, you know. Drinks of some sort." That seemed rather safe, really.