The Grunt is a bit of a mental case. Growing up His father was really abusive, and his mother stood by and let it happen. He grew up with many problems and fought the urge to become his father for years. Finally he cracked under the pressure of society and killed his family. Once in prison he lost his mind completely and became obsessed with the idea of eating people! After the apocalypse he was freed and became obese by overindulging on victims. You are just the next meal. He is the crazed Scavenger equivalent to the Support.