MBI ( M・B・I, エムビーアイ, Emu Bī A) is an abbreviation for Mid Bio Informatics, a powerful conglomerate founded by Minaka Hiroto, with their headquarters based in Teito Tower (帝都塔, Teitō-tō) and in charge of the Sekirei Plan. With the overtechnology ("Regalia" Kanji used for this), found in the alien ship on Kamikura Island, he built up MBI as a pharmaceutical company. Soon after this MBI became an economic, technological and medical network, controlling the world in every field . MBI has enough power and influence to take control of a huge city like Tokyo and to own and keep a company army.
- Minaka Hiroto: Founder and CEO
- Sahashi Takami: Head researcher and in charge of the Sekirei Plan
- Asama Takehito: Researcher (deceased)
- Ichinomiya Natsuo: MBI clerk and also Ashikabi of the Disciplinary Squad
- Miyajima: Special Advisor and Tsukiumi's tuner