Keanu Ikazuchi from Raikiri's family is actually the subject of the current chapters I'm releasing (subtle plug).
There's a lot more to their history, but it's not really relevant, unless I get off my ass and write the prequel I had in mind.
Keanu's mother, Mariko Ikazuchi, is the daughter of the Thunder Shaman, one of the five spiritual leaders of the Mercenary guilds.
Kekoa Puahiohio went to him to learn how to fight where he met Mariko, who he nicknamed Mari much to her annoyance. A student of the Shaman herself, Mariko also served as a mentor to Kekoa and his classmates, often putting them in their place.

Kekoa made a name for himself in the great Mercenary War; a war fought exclusively by Mercenary clans that brought the continent to near ruin. No ideology, no land gained, but purely for the sake of greed.
Along with his clan brothers, Kekoa was one of the three natural disasters, earning the nickname, Kekoa the Hurricane. Overtime his optimism was whittled away, finding himself fighting people he once fought and partied alongside torn apart by the different Daimyo vying for lucrative contracts.
Meanwhile Mariko came of the age to find a mate; the angel people are exclusively female and migrate to the land of Spartoi to find a worthy father for their children. Girls stay with the mother and boys are sent to live with the father in Sparta.
Wanting a mate she knew, Mariko asked Kekoa to father her children, offering a fancy sword as a dowery.
However he found himself despondent after nearly a decade of fighting, unworthy of becoming a father. After encouragement from his friends Kekoa accepted Mariko's offer, but asked to stay with her to help raise the children.
An unual arrangement for their race, but after killing so many he wanted to help give life for a change.

The pair gave birth to twins, Keanu and Kapua. Despite both having Spartoi names, they took the mothers family name of Ikazuchi.
For a while the family lived happily,
until the day an invader came to their home.


Kekoa fought the invader bravely but lost his life. Mariko was forced to defend her children, losing her leg in the battle. They were saved in the nick of time by Xin the Wildfire, Kekoa's war buddy. However Kapua was never seen since, presumed dead.
Keanu blamed himself for the loss of his sister, asking Xin to make him his apprentice and learning the ways of the mercenary.
Now living alone, Mariko turned her home into a hotspring inn. Despite Keanu visiting rarely, she keeps in regular contact with her son and Xin.