GlorianaGloriana have been making fans all across the country since opening for Taylor Swift on her Fearless tour this year, but apparently they made such an impression on one super-fan in Seattle that he decided to get on the bus -- well, under the bus -- to go on the road with them!

"There are bays underneath the bus," Gloriana's Mike Gossin tells The Boot. "This man managed to sneak past security and get under the bus in one of the bays. Tom [Gossin] went to go get some clothes, and he was hiding under the bus! It was so crazy and we have it on video! You should have seen him jump ... it was hilarious!"

Tom adds that he got a second surprise as well after the über-fan was escorted from the backstage area. "We had a camera crew on hand that day just by chance, they were filming webisodes for us. So apparently this guy's our number one fan --- his name is Dave. He was in my bay and I've been missing a couple of boxer shorts ever since ... I don't know what the hell's going on!"

Gloriana, whose latest single and video is the appropriately-titled 'How Far Do You Wanna Go,' are gearing up to join Taylor on the second leg of her tour in early 2010 ... hopefully with some heavy-duty locks on those bus bays!