Real name: does not remember
Occupation: spy
Identity: Secret
Legal status: complicated
Other aliases: innumerable
Place of birth: unknown
Place of death: innumerable
Marital status: unknown
Known relatives: none
Group affiliation: United States government
Base of operations: global
Height: average
Weight: average
Eyes: nondescript
Hair: usually brown
Unusual features: unmemorable
Strength level: human engaging in intensive regular exercise
Known superhuman powers: none
Weapons: small arms, sniper rifles, combat knives, strangle cords, poisons, grenades, explosives, hand to hand combat
History: Kilroy is a mysterious agent of US and Allied forces that was active during WWII and possibly even earlier. Serving as both a spy and a source of fear for the Allies' enemies, Kilroy left a sort of Zorro's mark, "Kilroy was here." The mark was frequently found by Allied forces when they first entered enemy territories and encouraged them that others had gone before and prepared a way for them to succeed.
It is assumed that Kilroy is not a single individual and that through the years the title has been passed from agent to agent. This is not confirmed.