Medusa

Medusa is a dragon goddess and one of the most dangerous criminals in the world, she takes part in the most important events during the series, acting individually and also as an ally of Ashtaroth. She strongly hates Mikami and Yokoshima, for they have been able to ruin her plans being "simple humans". Medusa is really smart as an enemy, so she has always been troublesome, becouse she tends to consider her rivals weak point, like trying to disband the Spiritualist comunity from the inside, or taking the fight outside Japan to avoid Shōryūki's intervention.