It's a Pump

Now that the Enjoji house lies in ruins, the Tsuchinoko shrivels in the sunlight and finally perishes. Momo approaches to confirm the worm is dead, only to jump as it stirs and disgorges the Kito Family, who have somehow survived. Scolded by the clan's head for slaying the creature even though it had eaten them, Momo moves to look in on Okarun and Jiji, but the volcano suddenly erupts before her eyes. The head Kito rebukes her again, noting that the village's tie to the Tsuchinoko was what kept the volcano dormant. When the elder recites the local prophecy, Momo deciphers its real intent and corrects her: the legend pointed to the spring at the hot baths. Acting on this, she uses her powers to drag the tail end of the worm's remains over to that spring and plugs it there with the creature's rear. Since the carcass can channel water like a pipe from tail to head, Momo dashes to the head, raises it with her power, and sends water spraying out to quench the volcano's magma.

The Mongolian Death Worm withers and, in dying, spits the swallowed Kito Family back out. The survivors berate Momo for killing it just as the volcano blows and the townsfolk flee. Momo works out that the Great Serpent legend had grown garbled over generations and truly described a geyser erupting as a warning of the volcano. Hauling the worm's body to the hot baths, she rigs it as a pipe to blast the magma with water while the Kitos give chase.

It's a Pump runs twenty-one pages across the Cursed House Arc of the Kintama Hunt Saga, published February 22, 2022, in Volume 6 and split between Episodes 15 and 16. Momo decodes the village legend and repurposes the dead worm as a giant hose to fight the volcanic eruption.