Well, that's a sweet pun worth buggin' someone with! Glad things worked out well there, but now I'm curious about her past antics and the blood moon phenomenon! How many times has she seen it happen, or its aftermath?
I don't think it happened during intercourse, Haneda himself wasn't sure how that got there. If she did it while he was awake, during intercourse, I'm fairly sure he'd notice that she bit him and sucked blood.