A young Taiwanese assassin codenamed "Glass Heart" committed suicide by jumping off a building, and her heart was pierced by metal fence. Miraculously, her life was saved by heart transplantation. During her recovery she began to experience strange dreams, which lead her to Japan looking for the donor of her heart, who happens to be Kaori Makimura, former partner of City Hunter Ryo Saeba. The author mentioned in the first tankoubon volume that Angel Heart only shares the same characters of City Hunter but not its continuation. The events are all parallel universe, therefore it has nothing to do with City Hunter.

Although Kenzaburou Tondabayashi is a 52-year-old bureaucrat, he is well versed in reincarnation stories where a protagonist suddenly awakens in a fantasy world. After being hit by a truck, Kenzaburou lands in that exact situation. However, what baffles him is the fact he wound up in the world of an otome game—as the young villainess and the daughter of a duke, Grace Auvergne. Fortunately for Kenzaburou, he is somewhat familiar with his new world, as it is based on the game called Magical Academy: Love & Beast. He was a proud father in his previous life, and he often listened to his daughter rave about the game's setting and characters. Armed with background knowledge and a lifetime's worth of dad skills, Kenzaburou strives to make the most of his new life, though his kind-hearted nature makes it difficult to fully embrace the role of a villainess.

Hana lives on the small island of Tonakijima, with a population of 600, and loves reading to the island's children. Mizuki, the president of the school's broadcasting club, notices Hana's talent for engaging others through her storytelling and invites her to join the club. As Hana embarks on this new journey, she experiences many "firsts" with the broadcasting club members, deepening her love for reading even more.

Special that can be found on DVD. Contains animation not reused in the TV series.