If 당신 had an invisibility cloak, what would 당신 do with it?

Freak people the fuck out.

go and spy on Helena Bonham Carter;D

I'd go and see what Dumbledore was always upto!

Snoop on the CIA because I don't trust those motherfuckers!

I would use it to sneak around and hide from people and laugh at them behind their back (literally). I would also use it to creep people out like Harry does with Malfoy.

I would explore the restricted areas in Hogwarts. Then I would use it to hex my fellow Slytherins. >:-)

use it to pull pranks and get a glimpse of the term papers

Bunk history

Explore the grounds at night and stargaze. ^~^