Jiro Suenami is a lieutenant in the 11th Division.
Jiro's Zanpakuto is called 'Kyuuketsuki' ('Vampire'), and its release command is "Drain". The blade becomes glowing red, and in this form has the power to absorb the blood that it spills from its opponent. This blood, converted into spirit energy, not only heals Jiro from any wounds inflicted on him but makes him stronger. However his Zanpakuto is also his Doll, and is released in this form with the command, "Reveal yourself, Kiri!" ('Mist'). The sword turns into a female shaped mist. In this form, Kiri has the power to expand and absorb spirit particles, increasing in power as she does. The Energy she gains is shared with Jiro. It can also be given to others if Jiro wished it.
Kyuuketsuki is a large, male, armoured, black skin demonic looking creature with horns and claws, opposed to the feminine Kiri. Both however are bloodthirsty. Kyuuketsuki especially is battle proned. Jiro compares him to raw power.
Jiro's bankai is 'Kyouryoko Kyuuketsuki' ('Powerful Vampire'). In this form, Jiro combines with his Zanpakuto and comes to resemble its spirit. He has greater strength and stamina in this form.