Die-Heart is a Daimon that was created from the heart monument at the affection contest. Die-Heart was sent to the affection contest in her Daimon pod by Kaolinite to extract a Pure Heart Crystal from the winners of the contest, who were Naru Osaka and Gurio Umino. She extracted Umino's Pure Heart before it was returned to him by Sailor Uranus and Sailor Neptune. Die-Heart summoned minions who could look like humans and invite them to dance before revealing their true selves and attacking. Sailor Moon destroyed Die-Heart.