Kang Chiwoo lost his life in an accident and got reincarnated as the son of a great demon lord in another world. Unlike his previous life as a map designer, he is now a loser named Kella. However, in a world where magic exists and having realized the dormant power of Kella, Chiwoo sets out to achieve his goal of creating his dream map that he couldn't make in his past life... Will Kella be able to create his own map while fending off his brothers who constantly try to kill him, the countless threats upon his life, and the pressure of those around him who want him to succeed the throne?