Muhyo & Roji's Bureau of Supernatural Investigation The BSI is an agency consisting of two boys named Muhyo and Roji who at first I found childish and annoying, but they grew on me. Made for the pre-teen shonen-jump market, this manga has it’s scary moments. The boys battle all sorts of creatures from the underworld. There are monsters that look like langoliers, a scary chair that eats your shirt - and then you, and some ghosts that look like giant sorting hats from Harry Potter.