Kibosh (MBTG)

Kibosh is the ruler of the Underworld and antagonist/anti-hero in My Brother the Ghost.

Biography
Kibosh is ruler of the underworld. One day he overhears there were the birth of twins, but finds it strange that it is both Ghost and human twins. He later finds their location, staying with their maternal uncles, the Ghostly Trio. Kibosh approaches the Seymour brohters and hteir newborn niece and nephew. Kibosh almost has the twins separated, but the Trio, in fear of their niece having an unwanting feeling that her parents abandoned her, manage to convince them to raise the children on their own because they are still close. The ghost allows it, but reminds them to keep her and Casper in the shadows of their true parentage.