Tenshi no Hane to Akuma no Shippo
てんしのはねとアクマのシッポ
A devil named Luca enrolls in a school for angels and forms a contract with an unusual angel named Haniel, becoming a knight of the institution. He is tasked with preventing a foretold "great catastrophe," but is restricted from leaving the school. To achieve this, he must work alongside others, including Lilith, an angel with red wings, to uncover what the future holds.