Just tried this.
Only I made it 20 minutes, and was really, really horny before hand. And I wasn't allowed to cum the whole time, which was hard. my jeans made it so my vibe was pressed pretty hard against me. I was defiantly quivering and squirming the entire time, trying not to cum and waiting for the alarm to go off!
I might have to try to do this again one day, haha.