Lord El-Melloi II's Case Files: Rail Zeppelin Grace Note - A Grave Keeper, a Cat, and a Mage

Waver Velvet – The boy who fought side by side with the King of Conquerors - Iskandar - during the Fourth Holy Grail War in Fate/Zero. Time has passed, and the mature Waver has now adopted the name of Lord El-Melloi. As Lord El-Melloi II, he challenges numerous magical and mystical cases in the Clock Tower, the mecca of all mages----- (Source: Crunchyroll)