By Lanford Beard
Updated July 18, 2011 at 02:38 PM EDT

Rob McCool will always remember his anniversary — and not just because it’s the day he married the love of his life, Jeanine. Nope, Rob will never forget that special day because Justin Bieber made a surprise appearance at his reception. According to TMZ, the tween heartthrob and his girlfriend Selena Gomez were walking down the beach in Malibu when they heard the Biebs’ hit “One Less Lonely Girl” coming from the party. So naturally, they crashed. Full video after the jump.

Gomez stayed on the sidelines as her boyfriend entertained the partygoers with his innate Bieber-ness, turning even the manliest of men into squealing boys. After the DJ announced his presence, Bieber took the mic and told the crowd, “We just crashed it. We heard a party so we decided to just come. So let’s party.”

Alas, he didn’t show off those golden pipes and treat the audience to an impromptu concert. He did stick around for several minutes, taking pictures with fans, bonding with Rob, and politely waiting for Jeanine to show up so he could help this “One Less Lonely Girl” have the night of her life.

So, PopWatchers, did the Biebs’ street cred just go up for you — maybe just a little? Was it surprising to see grown men acting like shrieking fangirls? Which celebrity would you like to crash your wedding?