The Najimu is a pitiless gang full of the richest criminals in Tekkan, the ones purely responsible for Tatsu's hazardous reputation. They are dirty, armed, ruthless and will ransack an entire neighborhood in one night. The Tatsu Samurai rarely take notice, probably because they are paid off by various Najimu bosses.

Their confidence is so towering they often cover themselves in tattoos to symbolize their position and to gain respect. The name "Najimu" comes from Tekkanese dialect meaning "to become familiar with; to fit in; to adapt oneself; to get used to; to grow accustomed to​" which represents their way of adapting to the horrid downfall in the Tekkanese economy. Some say they are also motivated by the Omen, an ancient yokai that lies in the deepest parts of Tatsu and accepts sacrifices in exchange for riches and fortunate rewards.

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