The leather carry bag is a thick, durable container used for discreetly transporting items. Kakita Kazumi utilized it to hold a black hemp bag found in the ceiling space of the Crane couple's quarters. The black bag contained a mild tincture of Firebiter poison, a forbidden contact poison, and was slick with an oily residue. Kakita Kazumi took precautions to avoid direct contact with the poison by using thick leather gloves to clean the wakizashi’s sheath before placing the black bag inside the leather carry bag.
While proceeding toward the tea courtyard, Kakita Kazumi carried the leather bag containing the black bag. The leather bag was left in the sun, which caused it to ignite unexpectedly. Kakita Kazumi attempted to extinguish the fire by throwing tea onto the burning leather bag, but it was charred beyond recognition, resulting in the loss of the concealed bag's contents.