Tear Jerker / Codename: Sailor V

• Sailor V's first kill is a youma whose disguise was the boy she was crushing on. And the boy never existed, it was the youma all along with an invented identity. And she had no choice but kill him to rescue her schoolmates and save her own life, as he had refused to surrender when she had asked him. No wonder that the first thing Minako does after that is to go home and cry herself to sleep...
• Danburite's death at Sailor Venus' hands in the final chapter, with Danburite putting into words that Minako will always choose duty over love, just as she had done by killing him. To drive home the point it's a tear jerker, this is the last time Minako cries in the entire manga continuity, as if she has exhausted her tears.
  "Is my fate to kill the man I love?"
• Danburite is also a Woobie, Destroyer of Worlds. He loved Venus in a past life, but couldn't win her due to being a low level soldier. In this reincarnation, he has to work for the Dark Agency, but his love for her keeps sabotaging his henchmen's schemes. Unlike Demande, who decided his obsession with Neo Queen Serenity would factor into world conquest, Danburite fails to pick a side and thus dies for his indecision.
• Minako's Character Development. At first she was merely a Tomboy with a Girly Streak and superb athletic skills who dreamed of finding love, had a few good friends and was decently popular in her class. Then her battle for justice starts, and by the end of the manga she's a Stepford Smiler who will always put her duty above everything else, even love, in spite of her very presence helping everyone else finding love, and her friends, including her childhood friend Hikaru, have all but disappeared.
• Not just her friends, but also her family. By choosing her duty over love, Minako abandons her parents and Hikaru to go and find the other Senshi in Tokyo. As far as we know in Sailor Moon, she never talks to her mother and father again. Who knows what they must be thinking every time Tokyo is attacked?