Rub
You use your fingers to hold the roof of the festival up, but it rubs against them. The roof is heavy, and you have to walk to keep up, so the roof is rubbing against them really, really badly.
Have you ever been to a Japanese festival? There's always one of those portable shrines that are basically just roofs people hold up. That's what you're trying to hold with your fingers as the whole thing rubs against them.
さつ
こす, す
None
Just when you thought the rubbing couldn't get any worse, Satsuki (さつ) appears and hops up onto the roof. AAGH! It hurts!
Picture Satsuki sitting on the roof as you carry it through the festival. She may be a little girl, but her extra weight makes the rubbing so much worse — you can really feel the skin chafing.