Samurai Spirits Zankurō Musōken: Zaniku no Natsu (侍魂斬紅郎無双剣 斬肉の夏), "Zaniku no Natsu" roughly translating to "Slaughter Meat Summer", is a short-story published in June 15, 1996 for Gamest magazine. The illustrator for the story is the mangaka, Rei Hiroe, who is best known for his work Black Lagoon. The story focuses on Shizumaru.
Shizumaru, melancholy and lost, wanders through the land in search of the demon he has no memory of. Panicked but skilled with his techniques in battle, he unintentionally kills many of his opponents. Not knowing what to do, Shizumaru travels again and repeats this ugly cycle with every new encounter. He is warned to stop his activities by Hanzo, least the boy become a demon himself.
Taking his advice but still confused, Shizumaru spends a day relaxing by the river. While trying to remember once more what the demon looks like, Rimururu greets him. Taking a rest as well, she introduces herself as a priestess of Kamui Kotan. Slowly getting past his embarrassment, Shizumaru replies that he is searching for a demon. Hearing the word demon, she talks about her sister who left her home for the same reason.
When she starts to describe her sister's personality, Shizumaru shakes as he remembers stabbing Nakoruru. In her final moments, she embraces him and pities his mistaken demon path. She prays that her blood will be that last that he will shed. Her last words were her apologizing to Rimururu. Shaken, he asks Rimururu her name and is mortified to hear it. He breaks down and confesses that he was the demon who killed her sister.
His apology gains no sympathy from the priestess, however, who attacks Shizumaru in a blind rage. During their fight, she realizes what she has done and cries for him to stop. He replies he can't once he smells blood and apologizes. His childish answer angers her further. Once she screams that she can't forgive him, he draws his blade and defeats her. A heavy downpour washes the scene.
He remembers Haohmaru's words about survival: his sword is his life and the guy who kills more people "wins" his life. Burying her body, Shizumaru apologizes and continues his quest in the rain.