Mini anime featuring characters from the Assault Lily franchise.

In a city of the dead, long since ruined and far from human civilization, lives a single human child. His name is Will, and he's being raised by three undead: the hearty skeletal warrior, Blood; the graceful mummified priestess, Mary; and the crotchety spectral sorcerer, Gus. The three pour love into the boy, and teach him all they know. But one day, Will starts to wonder: "Who am I?" Will must unravel the mysteries of this faraway dead man's land, and unearth the secret pasts of the undead. He must learn the love and mercy of the good gods, and the bigotry and madness of the bad. And when he knows it all, the boy will take his first step on the path to becoming a Paladin. (Source: J-Novel Club)

The OVA will tell the childhood stories of the main characters, adapting from the first volume of Satoru Yamaguchi's original light novel. Bundled with the seventh limited edition volume of the manga.

A letter is delivered to Lord El-Melloi II informing him of a Clock Tower reunion. One morning, as the reunion's date draws near, Lord El-Melloi II takes a look in the mirror and reels in shock. He is suddenly a full decade younger! Lord El-Melloi II has become Waver Velvet, his former self! Believing himself to be in the grip of a powerful, magically induced delusion, Lord El-Melloi II immediately begins investigating how this could have happened. On the day of the reunion, he makes his way to the gathering of his contemporaries, planning to confront whoever transformed his body and hoping to reveal their intentions. However, when Touko Aozaki arrives, things take a sudden turn... (Source: Crunchyroll)