CONTAINS SPOILERS

First, find the two robots on the roof throwing paint cans. You’ll be able to meow next to one of them, causing paint to drop onto the shop below. That shop is Super Spirit Laundry. The owner will come out and you’ll be able to go inside where you’ll find a bottle of Super Spirit Detergent. If you get lost, follow the signs that say “Super Spirit” on it to find the laundry shop.