The gaki are after the water these people are sprinkling for the souls of their diseased parents. Gaki, although forbidden from drinking regular water, apparently could avail themselves of water once it was sprinkled for the dead. The artist exhibits amazing skill at employing delicate shading to vividly represent the gaki, which no human has ever seen.
Lamenting his mother’s fall to the state of gaki, Maudgalyāyana, who was among the ten principal disciples of Gautama Buddha, visited the realm of gaki in order to deliver food to his mother and relieve her hunger.
But the food went up in flames the moment his mother reached for it. (Lower right)
These 500 gaki in India were tormented, unable to drink water from the Indus River, which would go up in flames whenever they approached it.
Then the Buddha appeared before them, a miracle not seen in thousands of years.
The Buddha preached to the gaki that their agony was the result of their actions in past lives.
The gaki complained, however, that their pain was such that it prevented them from concentrating on what the Buddha was saying.
The Buddha then used his supernatural power to give water to the gaki. Once they drank the water, the facial expressions of the gaki relaxed and became calm, and their bodies became well-rounded, just like human beings.
The expressions of gaki savoring the water convey their joy. Seeing that their thirst was quenched, the Buddha resumed his lecture. The gaki attained spiritual awakening as a result, and ascended to heaven.
Ananda, who was among Gautama Buddha’s ten principal disciples, was training when a fire-belching gaki appeared before him. The gaki complained of his great agony, so Ananda went to the Buddha for advice on how he might save the gaki. When Ananda followed Buddha’s advice, the gaki was relieved of his sufferings. This is the origin of the Buddhist ritual Segaki-e (lit. feeding the hungry ghosts).