In Japan, Ama divers are all female. Unlike average people who usually diving with the air tank, ama divers use no equipment but a special breathing technique called isobue when underwater. Ama harvests a lot of things from the sea, such as seaweed, sea snails, and abalone. Abalone in Japanese culture is believed to have a spiritual connection with Ise Jingu. Eating abalone contributes to longevity and youth and the deities like them. Tomokazuki is a sea demon who lures ama divers with abalone and lead to deep sea and drowns them. And it is said that Tomokazuki is a spirit of drowned ama. To protect themselves from the demon, ama sews symbols called seiman and doman on their cloth.