Marcus Damon

Marcus is presented as a fourteen year-old student who loves to fight. He lives with his mother and younger sister Kristy (Chika). Marcus meets and fights Agumon in the first episode of the series. When the fight ends in a draw, Agumon agrees to become his partner. Soon afterwards he's recruited as a member of D.A.T.S. As Marcus's partner, Agumon idolizes him and refers to him as his "aniki" (兄貴, a Japanese colloquialism for "older brother," used in this case with the connotation of "boss" as seen in the Yakuza).

Marcus is one of the few humans shown to fight Digimon by himself, though he still counts on Agumon's help to fight the stronger opponents. Even though other humans can evoke their Digisouls by themselves, Marcus must connect a punch on an enemy to do so, subsequently using it to digivolve Agumon.

Trivia

 * According to the first episode, his birthday is the same day as day Digimon Savers started in Japan, April 2.
 * Marcus is the first human lead character of any Digimon series (anime as well as manga) that doesn't wear goggles. Marcus is also the first "good" human to hurt a digimon on a regular basis.
 * His name is probably also an intended pun as it could be read Daimon Dai while daimondai means "big problem", which would make sense given his love for fighting.
 * He appears in quests of the game Digimon World D.S.
 * In the Japanese version, when referring to himself, Masaru adds -sama onto his name, which in Japan, shows great arrogance.

Masaru Daimon Daimon Masaru