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Tear Jerker: Yoko Tsuno
Yoko Tsuno has Daughter of the Winds, with Old Retainer Aoki's Heroic Sacrifice, Seiji Tsuno being unable to tell his daughter that the old man who took care of her as a little girl pretty much killed himself for her sake and asking Vic to do it instead, and Yoko being this close to an Heroic BSOD... The worse part went more of less like this:
Yoko: I... I was so selfish! So arrogant! And Buddha punished me by taking Aoki-san away!
Vic: No, Yoko! It wasn't you! It was Aoki himself who decided to do so! Don't blame yourself...
Yoko: I'm sorry! So, so sorry!
Also, Cecilia's backstory and Margaret's confession to Yoko in The Pray and the Shadow
The end of The Dragon of Hong Kong. Morning Dew's giant lizard pet has been killed and his body is swept away by the tide. Yoko explains to Morning Dew that he's leaving her for some marvelous place while fighting back tears.