"Serafi" is basically a Finnish version of the word "Seraph". In other words he is named after high ranking angelic creatures in Christian lore. The word itself can be translated into "burning fire" or "prosecutor".
Despite his angelic name, he acts quite the opposite. He is no angel, instead he is a mischievous little ghost. The name "Casper" would've probably fitted him better...
He has a funny habit of coming a cross as a tomboyish girl - no matter of his biological gender. Being a ghost, his favorite place in Marada is naturally the Undying Woods. His love of Tombola games blossomed first in the Woods, but his interest has since expanded to all the other Tombolas as well throughout the world of Marada - he plays all of them every day.
Apart from being a regular costumer on Tombola stands, he also puts his impish personality into good use while thieving around Marada. He is far from being a major criminal though. All he does is little innocent pranks here and there in order to make life more interesting for everyone. :)