Manga by author Katou Takuji

A mecha otaku is reincarnated into another world as Ernesti Echevalier (Eru). In this world, exist huge humanoid weapon known as Silhouette Knight. Dreaming of piloting those robots, Eru, with childhood friends, Archid and Adeltrud Olter: together they will aim to become Knight Runner, pilot of Silhoutte Knight.

He became a magical girl, and his buddy fell in love with his magical girl form

Is this how we deal with top-level adventurers?!The daily struggles of the Demon Lord's army in an "R&D Discussion" comedy!

Tales of Demons working in the Demon King Corps and a mimic aiming for the life of a adventurer.

The story of an immortal species girl who picked up a fleeting human.