Tengu Barai no Sankyoudai

Synopsis:

Yamaemori Mamoru, who is cursed to fight alone against terrifying Tengu beasts, is willing to give up everything to protect his younger brothers. Yamaemori Mamoru spends his days caring for his family shrine in the mountains above Japan, battling Tengu, creatures who consume human flesh, and ensuring that his two younger brothers will never have to take up his mantle. All he knows is that his life is a curse—he will die young while serving others—because he is unable to escape the life his parents have forced upon him and a sinister ceremony involving Tengu blood. However, Mamoru must balance being a caring big brother with being a mindless beast in order to combat monsters; otherwise, he runs the risk of turning into the very thing he has vowed to destroy.