The moth that has been haunting the Ipe family came out of hiding when Rahel and Estha were being interrogated. On page 300, "Inside the Inspector's room, Pappachi's Moth was on the move." As soon as Rahel and Estha walked in and saw Baby Kochamma in place of Ammu, the moth's icy wings touched their hearts, and the situation deteriorated. The way I see it, the moth is last of the small things, lost inside a world of big things. It was their misdirection and chaos that brought about the traumatic events (Orangedrinklemondrink Man, Sophie's death, Velutha's beating). Maybe this pestering moth is its own little God of Small Things. Or maybe its a reference to Velutha, trying to find his way in the maelstrom of the world of bigger things. This book can be analyzed in countless ways.