Willy is the only antagonist in Night 5 of Five Nights at Treasure Island.
Willy is a black and white incarnation of Mickey Mouse and looks similar to the Mickey in the cartoon, Steamboat Willie. He also appears similar to Suicide Mouse, however, his pants are different and his belly appears to be larger.
Willy is hostile. He can move throughout most of the locations. If he is found in the office, the player must shut down a camera.