Bambietta Basterbine is a Quincy and a member of the Vandenreich's Stern Ritter, with the designation "E."
In the Thousand-Year Blood War arc, upon receiving the orders of the Vandenreich Leader, she and the other Stern Ritter gather at the Sun Gate, before traveling to Seireitei in order to participate in the conquest of Soul Society.
Once there, she and the other Stern Ritter create pillars of blue flames prior to engaging the Shinigami in battle. Gleefully massacring a number of Shinigami, Bambietta is stopped by Captain Sajin Komamura, who remarks upon the little girl being in the enemy army. She retorts that since even a dog could become captain, Soul Society must be desperately short of soldiers.