Rivers of beer, clouds of pot smoke, but no Bieber. According to TMZ, Justin Bieber’s mansion in Calabasas, just north of L.A., hosted a massive rager last week, though the pop star himself doesn’t appear to have been in attendance. His friend Lil Twist, who was seen smoking weed with Bieber earlier this year, invited at least 40 girls and a few guys over to the Bieber palace, and TMZ obtained photos of dozens of beer bottles, bongs, and other incriminating evidence.