Hikari_no_nisshoku

Ringo's real name is Asahi but everyone has come to call him Ringo, the apple, because of his green vest, noticeable among the usual grey and whites of the army. The lad was a simple farmer to begin with until his sister caught a terrible illness that caused her to cough up blood regularly. In order to treat her condition he enlisted into the local army, too poor to afford the medicine required this seemed like the only choice, yet he was too poor to afford the uniform as well, so he found himself singled out by his green peasant outfit. Soon Ringo became the laughing stock of the cohort he served in, untrained, barely allowed to enlist, using only a stick for a weapon on his first battle, which he spent unconscious for the most of it.

Ringo swore he would have his revenge and earn money for his sister, and trained hard. He buyed chores off his colleagues and soon earned some kind of grudging respect, the hardship soon making him strong and fit. The green that had been his humiliation became his pride, as while he learned how to fight he got more bold, leading charges into desperate situations to try to get a promotion for the sake of his sister, to gather attention. It worked, much better than he had imagined it could work, as he managed to lead victorious charges one after the other.

One day the promotion came,landing him commander of his very own cohort but his sister's condition had gotten so bad that the medicine finally affordable was now useless. Gritting his teeth he seeked another way to heal her, to fight against death in yet another battle, be victorious. It came under the form of a solitary monk that accepted him as student, teaching him the ways of the light. Now harnessing the healing properties of the burning light within he finally was capable of healing his sister... However duty called, forcing him once again to lead into the fray, using his magic to blind his opponents and heal the wounded, earning yet another promotion and a title, hikari no nisshoku, the radiant eclispe.

The cheerful soldier eventually came home to learn that his sibling had disappeared, leaving a mysterious letter behind. Watever it said he found the letter sufficiently troubling to find himself deserting the military despite his standing to search after her, whatever happened is a secret not easily shared and mentioning the subject brings a dire cast to his face. Some say it's the same face he arbors when he must kill someone in battle...