Merio is an MS Paint abomination registered as Tribe #1. He is a cunt who constantly uses profanity against people and in general. He also wastes his time bashing religion. He's started Twitter feuds with literally every Christian church that has an official Twitter. These feuds are full of ad-hominem and homophobic generalization from Merio.
One day, Mario was signing into a hotel, which also had Donald Duck, Goofy, Pluto, Spiderman, and Homer Simpson living there. A bomb was then dropped which turned everyone in the hotel into MS Paint abominations, spawning Dolan Dooc, Gooby, Pruto, Spoderman, and Homor, respectively (in contrast to their previous forms), and Mario was turned into the Merio we now know. Merio's money was also turned into ranch dressing by the bomb, so he deals with financial problems. In West Korea, he has a different job every day.