Eimer has worked tirelessly to reach her goal and even set up a website, onelesslonelyprom.com, back in January 2011 in hopes of reaching the Biebs. She wrote articles, made rap videos with her sister, and probably hoped Selena Gomez didn't come after her. Apparently the tteen's seen Bieber in person twice, at various fan events, and decided the star was someone she could be friends with. So she set out to make it happen.

Eimer got some press from all of her hard work, but still hadn't heard back from Bieber when it came time for prom Saturday night. But, the teen got the surprise of her life when she discovered Bieber had gotten her invitation and left her a video response. Of course, that video played in front of all her classmates at prom. As far as we know, no one fainted on scene.

In the response, Bieber explains that he couldn't make it to her dance because he's going to the Billboard Awards. So, he arranged to have a car waiting for her and her sister so they could join him. In the morning. Screaming and hugging ensued.

Now, of course, Eimer's Twitter page is flooded with congratulatory tweets (and the occasional bitter, jealous jab). And, Bieber's been tweeting at her all day, too. "tired but up for rehearsal for the BILLBOARD AWARDS tonight. @cadyeimer see you soon :)" he wrote Sunday morning from Vegas.

"Hellllo Vegas :) @justinbieber Holli & I can't wait for tonight! it's gonna be a blast. thank you again :)" she wrote, after we imagine a very sleepless prom night.