Friends season 9, episode 13
Original air date: January 30, 2003

OK, playing a little catch-up on Friends:

After seeing Rachel kiss Gavin, the new guy from her office, across the way on Monica's balcony, Ross desperately tries to hook up with anyone he could find, eventually meeting this very needy, clingy woman who started referring to him as her "new boyfriend" about 20 minutes after they met. Rachel meets her, finds her weird, and Ross dumps the girl. He confronts Rachel about the kiss he saw, she says it was a one-time thing, he says "What about the guy you gave your number to at the bar?"

Rachel: "How do you even know about that?!"

Ross: "Because he called here."

Rachel, slowly, and with obvious anger: "Why didn't I get that message?"

And then she and Emma move back in with Joey.

Oh, yeah, Chandler's still out of work; Phoebe, Mike, and Monica sing at Mike's piano bar, and the patrons love Monica because her shirt is see-through in the stage lights.