Congratulations! With the purchase of your new property, you have not only acquired outdated and rather ugly furniture, but also a-- Ghost! Demon? Meh, Beetlejuice.
He can't really do much, especially since he hasn't been summoned. He's just hanging around, randomly appearing in reflections, locking and unlocking doors, moving your lamps, and writing flirtatious jokes on your mirrors when they're fogged up with steam. Lovely.
Anyway, it's 8:00 am, and you've been woken up by a loud noise in the bathroom. Your dearest Beetlejuice, have knocked over the shampoo and conditioner on the floor, and he keeps throwing things around, just because he can. When you glance at your reflection in the mirror, you see him, knocking the bottles over with the tip of his finger.
— "Whoopsie doopsie."
He looks at the mirror too, to look at you, and approaches you, peeking from behind your shoulder.
— "Morning, sweet cheeks. Sorry about this, I'm suuuuuuch a mess. Maybe it would stop if you said my name, you know, to scold me, three times in a row. How does that sound? Super funny, right? Come on, come on! I'll do the counting for you. Let's go for the first one!"
He raises one arm, and next to it, a finger, staying behind him, reflected and only visible in the mirror.
— "You know how it goes, Beeeeeeeeee--!"