Justin Bieber sings Justin Timberlake's famous breakup anthem, and we now have some MAJOR things to think about.

Justin Bieber has had an eventful past seven days to say the least. In addition to winning three EMAs, breaking up with Selena Gomez (UGH SADZ), and performing at the Victoria's Secret Fashion Show (Thing No. 3 may have had something to do with Thing No. 2), Justin still has to soldier on with his day job, which is being the biggest pop star in the world. So it DEF struck us as interesting when Justin whipped out a poignant cover of Justin Timberlake's famous breakup anthem "Cry Me A River" on the Boston leg of his Believe World Tour.

Watch Justin Bieber perform Justin Timberlake's "Cry Me A River" after the jump.

In the cell phone-shot clip, we join Justin as he's singing an acoustic rendition of JT's 2002 smash. We understand that the Biebs must be feeling rill raw right now, but after watching this video, we're suddenly left with so many pesky QUESTIONS! If "Cry Me A River" is originally about someone being unfaithful, then who would be the unfaithful party in the Selena/Justin equation? Could this have anything to do with Justin's wandering eyeballs at the Victoria's Secret show? And if someone was unfaithful, then will one of them release a new song about it? Will it be as good as "Cry Me A River"?? OK, OK. Maybe we should just slow down a bit. We'll just wait for things to unfold naturally (aka read a lot of gossip blogs and build our own stories because it's way more fun). In the meantime, we'll just enjoy Justin singing one of pop's modern classics -- and we'll worry about all these questions later.

+ Watch Justin Bieber perform Justin Timberlake's "Cry Me A River."

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