It all started when Cartman confessed feelings for Kyle. Than Kyle said he had feelings for Stan, than Stan said he had feelings for both of them. The 3 friends decided they should make it less complicated, and started a polyamorous relationship together (Without Kenny).

Cartman: why don’t you guys be good boyfriends for once and buy me some food?!

Stan: but all I have is 4 bucks…

Kyle: If it’s not a date, I’m not buying shit for you fatass.