Rimuru is an eccentric and childish person by nature but this shouldn't be mistaken for immaturity and naivety. Underneath the surface, Rimuru is constantly analyzing, planning, and weighing the pros and cons of their actions, taking the smart move in the long term over more rash and emotional decisions. In betrayal of this composed and calculative demeanor, Rimuru is ruthless when it comes to handling people who have aroused genuine fury inside of them.