Clumps, classified as Entity 5 in Backrooms lore, are writhing masses of limbs averaging about six feet (72 inches) in diameter. By contorting their bodies they can squeeze through gaps as small as two feet (24 inches), which makes barricading them out nearly impossible. Driven by ceaseless hunger, they go after anything within range.
The heart of the horror is an infiltration that cannot be stopped. A body that slips through any narrow gap combines with an appetite that never rests, and when starvation peaks they have been known to attack and even cannibalize their own kind. As a threat uncontrollable in both shape and behavior, it denies the very notion of a safe hiding place.