She decided to have a little fun with her bosses powers.

Arata decided that she would "borrow" her bosses keys.
Keys that, with the right passwords, would take the user to whatever world they wished.

Arata wanted to visit her bosses 3 favorite worlds. The world of the "Vongola", "Titans", and "Demon Butlers".

However Arata didn't just stop at a simple visit, she wanted a party, (or in her case a "battle royal") so in the middle of her visits she would take "them".

Right when Arata hit the last world with "them" in tough, the key stopped working, and everyone split up, and the only thing going through Arata's mind then was

"Boss is gonna kill me"