Millimos Saga: Battei Ouji no Tensei Senki

He was an ordinary office worker. One day, he was involved in a train accident. When he woke up, he had been reincarnated as Milimoss Nonette, the seventh prince of Nonette kingdom. He was gifted with magic and learned holy skills on his own, earning him the position of Marshal of the National Armed Forces at the young age of 12. Join the battle of the two largest countries in this world of magic and holy skills!

(Source: Mangamo)