 SCP-451, formerly Agent MJ, is a Caucasian male, 33 years of age and 1.6 meters tall. SCP-451 cannot perceive the presence or actions of other human beings. Changes made to the immediate environment are generally not noted by SCP-451 unless his attention is elsewhere for any arbitrary period of time. When changes to SCP-451's surroundings are misinterpreted, including all attempts to communicate with him and any clear evidence of direct human intervention, study may be necessary to determine a pattern in what is perceived and what is not.