Texas Lawyer [journal] Gloss. of Texas Prison Sl. 8 Feb. n.p.: Blood-In, Blood-Out – Term for the requirement of performing some task for a gang (such as carrying contraband, hurting or killing someone) to gain admission into the gang, and the requirement to perform a similar act to get out of the gang. A gang member who attempts to get out of the gang without following the blood-out requirement will have a hit placed on him by the gang.at blood in, blood out under blood, n.1