Martini of Another Realm

Synopsis:

During World War I, Austro-Hungarian technical soldier Lewis Henry is obsessed with designing and manufacturing firearms. Shortly before the war ends, he is struck in the head by a dud from an Ilya Muromets heavy bomber. Bitter and frustrated that his ambitions remain unfulfilled, he makes a pact with the evil god Atu and is reincarnated in another world. In the identity of a woman, he begins a journey to reclaim his dreams in the royal city of Casforen.