Tsutomu is a young Duelist from Domino City, who gets pulled into the World of Darkness by Trueman.
Tsutomu complains after being made fun of by his peers for being a weak Duelist. Trueman appears before him and takes him to the World of Darkness. Afterwards, Trueman took on Tsutomu's form, scaring the boy's parents. Trueman used his form to trick Axel Brodie in Domino City when the latter went there in search of clues.
Though he is not shown Dueling, the following cards can be seen on his desk before he meets Trueman, or on the floor after Trueman appears. He apparently uses a Water Deck.