It's all rather self-explanatory. This is the Gata Bar. It just opened in Tokyo's Aoyama for a limited time. The bar features mineral-rich clay from Saga Prefecture, which holds a mud Olympics during the summer so locals can have fun and cool down.
The bar recommends bringing a change of clothing (such as swimwear) as well as a towel.
The bar is also serving sake and beer from Saga.
The Gata Bar will be open to the end of July.