Katanagatari Season 1 Episode 6

Kanazuchi, the Twin Swords

Shichika and Togame find themselves in the harsh Ezo region in search of the enigmatic Itezora clan. Unfortunately they soon discover that the Itezora's village has been destroyed and the only survivor is an incredibly lonely and immensely powerful 11 year old girl who now possesses the Kanazuchi sword they are seeking. Things then take a dangerous turn when Kyouken Maniwa arrives to claim the Kanazuchi sword and get revenge for her fallen comrades' forcing an already injured Shichika to engage in his most dangerous battle yet.