I bet Miyuki is the kind that can't control herself.
You know, cumming when you're only teasing her supple breasts, then forcing you down, tearing your pants off, and quickly shoving it in your ass. Of course, she'd come right after inserting it, but she wouldn't stop there. She'd keep going until she completely emptied her balls into your anus. When she finished, she'd pull her spent, half-erect cock from your ass and make you clean it with your mouth, then pass out shortly afterwards.
Just a thought.