In the Belly of the Beast is a trophy/achievement for the Zombies map Zetsubou No Shima. It requires the player to "survive being consumed".
In order for this trophy/achievement to unlock, the player must be eaten by a Thrasher, and have a teammate kill it before the player bleeds out. Alternatively, it will unlock if the player bleeds out while consumed, and the player's team survives, making the player respawn in the next round. If a player uses an Imprint Plant to revive themselves after being eaten by a Thrasher, they can also earn the achievement.