One of Eiden's clan members, Yakumo is a serpent yokai who has inherited immense power. Warm and respectful, he is also an excellent cook. What he fears most is losing control of the heavy power coursing through his veins, so he is very careful to keep his temper in check. However, when angered, he is truly a force to be reckoned with.

While on his way to investigate alongside Eiden, he is unexpectedly pulled into a ripple leading to another world.