I was grounded because my room was pretty messy not gonna lie and she told me to clean it before I drove to a nearby town (4 Hour Drive) to see a concert. I came back and my xbox was gone. Pretty juvenile I know but she still thinks im 9...
Sounds reasonable to me, next time clean your room.
It would be funny if his mom took the Skyrim game too.

Next time she might not just take the xbox away, she might actually play your game, deliberately screw up your questline, get your character arrested, sell all your loot for 52 gold, eat all your sweetcakes, save the game, and then delete all of your previous saves. Because that is what I would do.