We wouldn't be talking about it if it was mentioned. It's a really easy, sly and effective way to make readers more engaged.
And it would't have worked with the punchline.
Bet the ghost's personality also changes to something lewd when she's noticed :02:
I'm kinda afraid the next two chapters aren't enough to bring the story to a nice conclusion. Oh why oh why such a sudden end!
At least one whole volume worth of lovey dovey fluff please :meguuusad: