It was right after the game and we made a huuuuuge comeback (we killed the outer most turrets, and we just barely survived after they killed all of our turrets and inhibitors and were starting to whack at the Nexus), the Xin kept saying that the Teemo was bad, the Teemo was feeding, the Teemo didn't build right, we're going to lose, blah blah blah, and I kept defending the Teemo (i.e. telling Xin that Teemo was fine since he had a higher kda than the Xin), and we ended up winning. After the game, in the chat, Teemo said "sona tq", followed by "that was a fun game" or something like that, and then everyone left.
Joy's explanation would make perfect sense though.