From Go! Comi:

Jack, a healer who's seen enough of war, has built his house far away from everyone to avoid facing any more destruction and death. He never expected to see another person so far up in the mountains -- especially not one with wings! The discovery of Hello, a young boy with distinctly bird-like features, sends him off on a sudden journey of hope, sorrow, danger, and the desire to save a doomed race from extinction. But fate is a tricky thing, and starting a new life with the remarkable tribe may have sealed his.