Wolf's History
Some two decades before the game's main event, Sekiro was found by Owl in the calmed battlefield, seemingly orphaned from
Isshin Ashina's coup and reclamation of his clan's homeland. Owl dubbed him "Wolf" and took the boy in as a foster son while having him trained (with the help of several co-mentors such as
Lady Butterfly) to become a Shinobi. Owl indoctrinated Sekiro with the Iron Code, which bids that
Father is Absolute, and a master comes close second.
Sekiro was at one time, appointed as Shinobi of the Divine Heir, which bound him to a lifetime duty of protecting his young lord. This responsibility took Sekiro under difficult times when Hirata Estate fell under a very timely attack by a bandit group under Juzou the Drunkard which unbeknownst to many, had the backing of Interior Ministry's agents and Sekiro's own traitorous father. The exact thing that transpired that night is unknown since Sekiro's memory of the event itself was gone from him, but it can be accepted that Sekiro was fooled by his foster father to think that he was about to pass away from wounds and was tasked with a "dying wish" to retrieve the Divine Heir, Kuro, from the hidden shrine beneath Hirata Estate's main building. For whatever reason, Sekiro was antagonistically greeted by Lady Butterfly, who does not seem to be content with Sekiro getting away with Kuro, and was forced to kill his former mentor. Victorious, Sekiro was somehow stabbed from the behind by a large Odachi and he fell to a near-death state. It was at this time, Kuro gave him his oath-bound immortality, allowing Sekiro to survive the harrowing event.
With no recollection of that night, Sekiro was left with no purpose to live. He was branded a rogue by the Ashina military, possibly due to accusations of betrayal involving Hirata's destruction that wasn't his doing. For an unknown amount of time, Sekiro spent his time in a well not far from Ashina Reservoir, wasting his life away in solitude. The soldiers and guards who came to know his presence went as far as to tolerate him, believing he lost his will to live. Yet, a letter from a tenant of Ashina Castle made its way into the well one day, informing Sekiro that his master is alive and need saving, from which point the game unfolds.
