A random fact for you: the most-forgotten items by customers at Saitama's Tamagawa Onsen are towels. To coincide with the rainy season's arrival, the onsen is hosting a teru teru bozu event throughout June which will see these forgotten towels repurposed into traditional dolls meant to prevent rainy weather - the ultimate upcycling effort!
If you're an onsen regular here and happen to see one of your towels turned into a teru teru bozu, never fear - just let the staff know and they'll return it to you.
At the same time as the teru teru bozu event, a colorful 'umbrella sky' will decorate the terrace area of the onsen. It's the perfect way to dissipate some of the rainy season melancholy!
I think as long as I'm dressed for the weather it's okay!