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Tear Jerker: Air Master
Sakiyama Kaori, whose extreme temper and confidence is a source of comedy, gets two of the most touching moments within the series. In her second fight with blood knight Maki, she refuses to give up, even after losing badly, her unstoppable rage becoming useless, and on the brink of death. Sakiyama Kaori is saved from Maki's killing blow by Maki's friend Renge. Sakiyama tearfully holds an unconscious Renge, realizes she can never defeat Maki, thanks Renge for saving her life, and falls asleep. A few episodes later, Sakiyama confronts her rival from high school. A flash back reveals that Sakiyama was made deaf in one ear by this rival, a fact the rival uses to torture her. If you know what kind of person Sakiyama is, it will break your heart. However, the following beat down makes it all better.
Maki's mother dying in a flashback in episode 27. You cried too... admit it.