Shiro no Koukoku MonogatariLegend of the White Kingdom; Tales of the White Kingdom; 白の皇国物語

Having lost his money, lover, and future, a man who has given up on everything finds himself reincarnated in the kingdom of Altodestenia. He, Lectival, has no memories prior to being saved by Meriela, the daughter of an aristocrat, and now finds himself rising up to save the kingdom in its current crisis.