His first appearance is as a humble emissary of his mother, Izanami, to the Dreaming coming with hopes of acquiring the Key to Hell that Dream of the Endless was in possession of. As he failed to acquire the key, he was meant to return home, but was impersonated by Loki who changed his appearance to fool Odin and especially Thor, as Loki stayed in the Dreaming Susano-O was temporarily installed to take Loki's punishment for the killing of Balder before eventually being released. Loki's reasoning for picking Susano-O was that he was a thunder god, and because of Thor, Loki has a dislike for thunder gods.
Some time later, Lucifer Morningstar enters Izanami's realm in search for his wings. Which Susano-O had traded from Remiel and Duma, the rulers of Hell. Susano-O acts as the primary speaker for his silent mother and strives to appear the gentle host while plotting Lucifers demise, sending the demon Musubi and his brothers to kill him. To his immense shame, all of his ploys are undone by Lucifer's silver tongue, the one power he still had in this realm, and he is eventually forced to return Lucifer's wings.
The event changes Susano-O and he vows to take revenge over Lucifer before preparing for the task.
In Persona 4 Susano-O is the ultimate Persona of Yosuke Hanamura.