There exist few humans in this world with the ability to manipulate their souls to form powerful weapons. Dubbed "Blazers," these people study and train at the prestigious Hagun Academy to become Mage-Knights; among the students is so-called failure Ikki Kurogane, the sole F-rated Blazer. However, when the worst student in the academy sees Stella Vermillion, an A-ranked Blazer who also happens to be a princess, naked, she challenges him to a duel with dire stakes—the loser becomes the slave of the winner. There’s no possible way that Stella can lose, right? Rakudai Kishi no Cavalry follows the story of Ikki as he tries to prove his strength to a world that believes him to be the weakest, all the while gaining new friends, wisdom, and experience. [Written by MAL Rewrite]

Legend tells that when the Earth was destroyed, the great clockmaker Y made a replacement from cogs and gears. Naoto Miura is a young boy who aspires to be a great clockmaker. However, despite his unique talent—sensitive hearing that can immediately understand clockwork mechanics from noise alone—he has made little progress. But this changes when a coffin falls from the sky into his apartment, revealing RyuZU, a female automaton forged by Y himself. News of RyuZU's arrival brings Marie Bell Breguet, the gifted heir of a distinguished line of clockmakers, and her cyborg bodyguard Vainney Halter into Naoto's life as well. When she and Naoto both become embroiled in an action-packed battle for their lives, they discover an uncomfortable truth: the clockwork planet that humanity has lived on for over a millennium is beginning to break down—a secret that many people will kill to protect. [Written by MAL Rewrite]

Within Cardia Beckford's hazy memories, she can recall her father Isaac and the home where she lives alone, feared as a monster by the townsfolk—for in her body, she carries a deadly substance. Embedded in her chest by her father, the eternally beating heart—also known as Horologium—has the capability to produce infinite power. However, it also makes her skin destroy anything it touches. Many in London seek the Horologium, including the terrorist organization Twilight, with whom Isaac is rumored to have close ties. To obtain the Horologium's power, the British military forces Cardia to leave her home as their prisoner. But on the road, she is whisked away by the gentleman thief Arsène Lupin, who says he will steal her heart. Joining Lupin and his companions, Cardia begins a journey to discover the truth behind Isaac's connection with Twilight, her missing memories, and the Horologium within her chest. [Written by MAL Rewrite]

On his high school graduation day, Itsuki's cousin, Mahiru, tells him that she's pregnant. Just then, a gate of light emerges and transports the two into the world of Granvania. In this land, "Impurities" have been causing a disturbance to the Stars, ultimately plunging Granvania into chaos and disorder. And Itsuki, now revealed to be one who is fated to meet with the "Star Maidens," is seen as Granvania's last hope and was thus given the task to produce "Star Children" and combat the "impurities." And unless the task is complete, Itsuki may never be able to return home. (Source: Wikipedia, edited)