kaiko sareta ankoku heishi (30-dai) no slow na second life
解雇された暗黒兵士(30代)のスローなセカンドライフ The_Slow_Second_Life_of_a_Dismissed_Dark_Soldier_(age_30) Ankoku_Heishi
Originally a japanese webnovel by 岡沢六十四. Has been adapted to a manga.
official novel illustrations done by sage_joh
manga artist is rurekuchie