Izanagi with his spouse and younger sister Izanami gave birth to the many islands of Japan (kuniumi), and begat numerous deities of Shintoism (kamiumi). But she died after giving birth to the fire-god Kagu-tsuchi. Izanagi executed the fire god with the "ten-grasp sword" (Totsuka-no-Tsurugi). Afterwards, he paid his wife a visit in Yomi-no-kuni (the Underworld) in the hopes of retrieving her. But she had partaken of food cooked in the furnace of the Underworld, rendering her return impossible. Izanagi betrayed his promise not to look at her, and lit up a fire, only to behold her in her monstrous and hellish state. To avenge her shame, she dispatched the lightning god Yakusa no ikazuchi no kami (Raijin) and the horrible hag Yomotsu-shikome to chase after him. Izanagi escaped, but the goddess declared to kill a thousand of his people every day. Izanagi retorted that a thousand and five hundred will be born every day.