Mizuki Shigeru manga
3, Street of Mysteries explores the fantastical-poetic vein that has forged Mizuki's reputation in Japan. The stories contained in this series hold in common the obsessive ideas of immortality and of life after death. Skillfully blending a range of black humor, drama, and questions of morality, Mizuki shows once more his profound understanding of the human soul. (paraphrased from Astiberri)
Youkai are specters who have lived in the human world since the dawn of time. They often rest peacefully in their dwelling places, until humans rouse them by inconsiderate actions. Kitaro is a young youkai boy who wants to help humans and youkai live in harmony, and he fights to protect humans from the enraged youkai who lash out at them.