“Want fuel. Want air. Want burn. Want to burn. Want to burn. Want to burn!” It repeats, growing louder and beginning to move about containment area rapidly, apparently searching for a way out.

It appears to be a sentient being composed of flame. SCP-457's actual composition is unknown, and has proven to be invisible and undetectable by any known means, but is shaped out by the flames it produces, often assuming a human-like form if given sufficient fuel to assume that size.