Pensentery
Pensentery is the act of inserting a pen, pencil, writing utensil in between the the buttock cheeks (or more commonly known as ass crack), walking around and setting it on the desk or where it is readily available of someone you dislike.
So yeah, I payed her back, grabbed the pen on her desk, the one she uses every day and pensentery -ed it! Walked around the office for like 10 minutes, all sweaty. You should have seen the weird face she made when she used it.