Boomer is Brady's twin and the co-king of Kinkow. He is more childish and brave than than Brady although he is not as serious and usually not as smart. It usually varies who's the one believing in mythical stuff. Brady believed in ghosts and Boomer didn't believe it at first until he was possessed in "Brady Battles Boo-Mer. Boomer believed in Boogey-Man which also turned out real in "Mr. Boogey Shoes".
Boomer likes to dance and believes to be very good at it and has a dream of becoming a club and had a couple of experiences like The Boom Boom Room and Club Co-Closet they were both mentioned in "Pair of Clubs". Boomer also believes he is very good at singing but it turns out that he is very bad but Brady is good.