The Bloods are first seen when the Crips, whom Jimmy Valmer and Timmy Burch asked to join because they thought they were "crippled" from birth, tell them to "pop some punk-ass Bloods". Jimmy and Timmy accidentally cause a tanker truck to crash into a group of Bloods, killing thirteen of them, which results in the Crips allowing them to join their gang. Later on, a few of the Bloods retaliates by attempting to kill Jimmy and Timmy in their houses in a drive-by shooting, though they are unsuccessful. As a result, Jimmy and Timmy decide to rent out the rec center in South Park and have the Crips and Bloods locked in together in the local recreation center until they resolve their differences. While they are initially hesitant, they soon realize that the two gangs have a lot in common, and they end up making a friendship with each other, including singing and playing basketball.
The Bloods consist of primarily minority characters who wear red-colored shirts and bandanas and have a few tattoos.