Serena runs to Blair and they have a conversation like this: Serena says, "I need advice." Blair says, "What kind of advice?" Serena says, "Like how does Gossip Girl know what it's like down there. And who told." Blair says, "You don't have any diseases, she's just being gross." Serena says, "Except for that time she said poop she mostly keeps it clean. I think this is a lie." Blair says, "You being a whore is not news. This will blow over. Now, get to class." Serena says, "What is that and where is it?"
Blair thinks more and says, "Unless one single person we know goes to the health clinic today, and then it means you have AIDS." Serena says, "What if I see three crows fighting over a piece of bread?" Blair says, "It will rain. Chuck Bass, also." Serena says, "Why are we talking about Chuck?" Blair says, "Because I will be this lady's assistant and that will defeat Chuck somehow." Serena says, "I love that lady!" Blair says, "She is a human shield." Serena says, "Good point. I am going to go sit outside the health clinic and hope everybody we know doesn't show up there. Because I am proud of myself. And because I am One Less."
Juliet is amazed that everybody on this show slept with everybody else on this show. Dan and Nate hold hands behind her back and woggle their eyebrows, and then they both say that yes, they are all one big nasty rat king but that in this case they didn't bone Serena, separately or as a team, in a very long time. Juliet says now she can't sleep with him some more so her brother won't get mad, so this technicality doesn't actually matter at all because "symptoms can be dormant for months, or not even appear at all," and Nate could still be a carrier. Symptoms of what? Carrier of what? DOESN'T ... MATTER.
I love how they're like, "It's a CW show, let's educate the kids about what's the what" but then left out the what of that what.