- In The Foam of Dawn, as an 8 years old child, Yoko asks his grandfather, Onoué, to try to create the diamond pearl once more, after decades of many failures. Onoué agrees on the insistence of the child and spends the next 6 years thinking about possible outcomes, past failures and reminisce of old feuds he had with his family. After 6 years, the oyster finally created the diamond pearl, only for Onoué to pass away a few months later. Yoko was devastated, as she came to realize her childish dream of having his grandfather succeed led him to waste his remaining years worrying. Even worse, the family decided to keep the diamond pearl's existence a secret in order to avoid unwanted publicity and prevent the pearl from been sold away to prospective buyers. No one will ever know of Onoué's success.
- 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
- Monya's father death. After being exposed to unknown radiations for some time, he felt ill and gave Monya her mission to save the world. Monya brushed it aside and was determined to save her father by programming the medical robots to heal him. Next morning, Monya went to check on him and found out that the treatments failed and her father died. She wept on his body for hours. Monya was now the last remaining human alive on Earth. It's truly heartbreaking since Monya's father was practically the only person she ever known.
- 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.
- After The Temple of Immortals, Khany, Poky, Myna and all the Earth-bound Vineans will never return back to Vinea. Ever again.
Tear Jerker / Yoko Tsuno