Amanda, Avery, and Gabriel agree to meet over lunch to discuss what to do with the house. Prior to their meeting, Avery traces the lines of the past to discover the origins of the house: it is its own thing. No one "made" the house live, the way Avery can summon consciousness to the objects in his own home. There is no curse or spell. This sort of awakening seems to be a thing that happens, much in the same way vampires happen, though Avery doesn't know why this house and not any other.
The three meet by Jack's Fish Spot at Pike Place Market. During the discussion, Avery gets up to head to the bathroom and hears ominous groans and smells terrible smells. When the stall at the end explodes, exposing an actual shit monster, he runs back to his party but fails to give them a coherent explanation before the shit monster shit-shimmies out of the crapper.
Gabriel, an old hand at shit monsters, immediately begins throwing grenades to create an anti-magick field. Amanda can't attack it as directly as he can, but she can make its matter fall apart; Avery focuses on trying to strengthen the Gauntlet to keep it contained.
The shit monster shit blasts Gabriel for his troubles, splattering some on Avery; Amanda, who really didn't want to get shit hit, throws herself to the side. All around them pedestrians shrieked and fled, or were knocked unconscious under an ambush of shit. The shit monster created a shit storm, sending parts of itself into the air and letting them rain down on the crowd, including Avery and Gabriel.
Finally, Gabriel's anti-magick killed the power animating it, turning it into nothing more remarkable than a large pile of shit. Fearing the Technocracy come to clean up the mess, Amanda and Avery fled, getting out with some not-coincidental luck. Gabriel chose to remain behind, getting cleaned up by the Technocrats who spun a story of a gas leak and mass hallucination, though the effect didn't take hold on Gabriel.