Gossip Girl episode 8

In this episode is Blair's birthday. Her party was like Chinese style and Serena invites Dan, who invites Vanessa. Serena tells Dan that she wasn't ok with the idea of Vanessa and Dan tells her that she has to try having a good relationship with Vanessa. Following this words, Serena dares Vanessa to play Guitar Hero.
Going to Blair's stuff, she  bet with Chuck that if Nate arrives at her party by midnight means that he loves her, but if he doesn't Blair will be all Chuck's.
Nate didn't arrive at the party, he almost get inside but he saw Jenny and when's for a walk. He shows Jenny the familiar ring that he suppose to give to Blair and tells her all the truth: he doesn't love Blair.
So, Blair had sex (one more time) with Chuck and Serena sees them.