Mameo

Mameo (マメオ), originally known as the Black Knit Cap Man (黒いニット帽の男), is a mysterious man. His true name is unknown, but Luche calls him Mameo because of the Mamemon print on his hat, and he himself adopts the nickname afterward.

Appearance
Mameo is a young man with fair skin, brown hair and blue eyes. He wears a black knitted hat with a white Mamemon smiley face on it, a yellow and black hooded shirt with long sleeves, black pants with yellow pockets, and black sneakers with yellow soles.

Description
Mameo carries a that was presumably his partner Mamemon. Unfortunately, it is stuck in that form due to the BH Program.

Digimon World -next 0rder-
Mameo never gives his proper name in the game, but everyone calls him 'Mameo' after Luche mentions the Mamemon patch on his hat. It is strongly hinted, but never outright stated, that he is the original protagonist of the first Digimon World game; he not only dresses in a similar color and style, but mentions having saved a Digital World before (but not the one featured in Next Order) and as a reward, being able to use the Digital Dive to return as and when he wishes.

He first appears in Server Desert, trying to restore a Gotsumon that had been infected by the BH Program with a basic antivirus, but fails. Shiki/Takuto, Kouta and Himari come across him while he does this, and assumes that he is the human behind the unexplained Machinedramon attacks. After the protagonist defeats the Machinedramon, he introduces himself and his partner, who is stuck in Digiegg form because of the BH Program infecting it.

Brought back to Floatia, he explains that he was attempting to remove the infection, but failed. He passes on his prototype antivirus to the protagonist.

At the end of the game, he confronts Shoma Tsuzuki, who reacts strangely to his presence; whatever is possessing him recognises Mameo as the kid that defeated him once before, and is purged from Shoma. It is later revealed during Reincarnation that he is Shoma Tsuzuki's homeroom teacher, and that he teaches Japanese in Shoma's school.