Yakumo being quite timid, nobody expected him to be that dangerous. After all, Yakumo kind of looked like a lost puppy when he wasn't following you around.

But it took one prank for everyone, especially Kuya, to realize Yakumo was actually quite powerful. When he got angry, Yakumo was unstoppable. His timid demeanor completely vanished, and suddenly, it was obvious he was a descendant from the Great Serpent.

Yakumo's essence was overwhelming: dark, thick, and cold. You watched as Yakumo snapped at Kuya for this one-too-many prank, not sure on how to help.