Challenge: Walls? Really?
Yes. Specifically, bathroom walls. They get gross. They get hairsprayed. They get damp and mildewy. They get, well, they’re bathroom walls. Figure it out.
Take 10 minutes with a rag with cleaning solution or some cleaning wipes (and if you use the strong stuff, make sure you’re wearing gloves and are working with good ventilation), and wipe down your bathroom walls. Top to bottom. As far up as you can reach. Even the grody parts (save those for last, though, so you’re done with the rag after that).