The Demon King's Hourglass – Reborn as a Fairy and Claimed by the Future Demon King
Maou-sama to Sunadokei ~ Tensei Shitara Yousei-san de Shourai no Maou ni Yama reru Hanashi ~ / The Demon King and the Hourglass: A Story about a Fairy Who Is Reincarnated and Becomes a Demon King in the Future / 魔王様と砂時計～転生したら妖精さんで将来の魔王に病まれる話～ / Maou-sama to Suna Tokei : Tensei Shitara Yousei-san de Shourai no Maou ni Yamareru Hanashii / Maō-sama to Sunadokei ~ Tensei Shitara Yōsei-san de Shōrai no Maō ni Yama reru Hanashi ~ / The Demon King and the Hourglass
Reincarnated as a fairy in an otome game world, Eleanor is found in the forest by Louis, a gifted boy destined to become the final-boss demon king. He lives with his sickly sister and already shows talent as a court magician beyond that of adults. Louis keeps the palm-sized Eleanor in a cage, but she can grow to the size of a human woman by drinking his blood. He pours an intense, possessive love into her, while the story raises the question of what this handsome, promising boy truly wants in this world.