He was cursed by Yamata-no-Orochi and traveled through the underworld. Ibuki-douji was the one who rescued him and returned him to the human realm. The curse placed on him was passed down in the Koga Mochizuki bloodline.
Koga Saburo
甲賀三郎
Fate/Grand Order -Epic of Remnant- Pseudo-Singularity III: The Stage of Carnage, Shimousa – Seven Duels of Swordmasters



























