Maruss (マルス, Marusu) and Rembrant (レンブラント, Renburanto) are a team who end up pursuing the team of Tia and Megumi early in the Mamodo fight. Their element is metal. Maruss was originally Tia's best friend in the Mamodo World, caring and looking out for her, compared to her bullying ways against Zatch. But once in the human world, his mentality changes, believing that friends can no longer be friends due to the nature of fighting and must go against one another to become king. Rembrant is a power-hungry, blithering idiot and a Middle aged dutchman who believes he can rule the world with his mamodo Maruss.
Maruss is a mamodo with long, blonde, curly hair and red eyes. His outfit consists of a purple vest with a buckle on it and a white shirt with a blue tie. He also wears brown shorts, with white long socks with black pirate shoes. Maruss appears to have very sharp teeth when he's in the human world.
According to Tia's past with Maruss in the Mamodo world, it showed that he was caring, kind and friendly back then but his attitude changed dramatically ever since the annoucement of the battle for Mamodo King took place, As a result Maruss has become more ruthless, cruel, violent and rather prideful ever since he participated in the battle for king and arrived in the Human World, He can also be impaitent, bossy, bratty and even desperate whenever the tables are turned against him. When Zatch (who he had formerly bullied) was able to not only hold his own but actually gain the upper hand he became enraged.
When Tia and Maruss meet for the first time in the human world, he betrays her easily and attacks her, sending her into the ocean. When Tia survives and is taken care of by Megumi, they start to pursuit her and attack them on many occasions, due to Megumi being a famous idol. While assaulting Tia in the midst of one of Megumi's concerts, Zatch comes to her rescue by standing up to Maruss until both their bookkeepers arrive to fight the battle against him. Ultimately, it is Zatch, the former "weakling" neither he or Tia cared for, who defeats the prideful Mamodo, and forces Tia to change her ways about friendship in the heat of battle.