She plumps up the sofa cushion.
The kitten curled up on the sofa cushion.
Now you're into money, possessions, earnings, major expenditures, cash flow and searching for loose change under sofa cushions.
Even though some of this would have to go in lowering marginal rates, it is a little like finding money behind the sofa cushions.
'Then it's all over,' sobbed the Toad, crying into the sofa cushions. 'I shall go and enlist for a soldier, and never see my dear Toad hall any more!'