New very fancy supersento. Inside and outside the decor and architecture is clean and modern looking. In the rear is a giant faux rock wall that has three waterfalls, multiple trees and a rainbow (hence the name 虹). The main large bath is upstairs and somewhat small. The best baths are a row of Shigaraki made egg shaped tubs that look out on the waterfall the bottom of the tub is porous and air is pumped through the bottom giving the tub a carbonated water effect like none I’ve ever experienced. The hot spring here is decent. Not the best spring ever, but very comfortable and used in a good way. This supersento’s most unique feature is the 8 family baths that are available. The baths are advertised on light boards much in the same way rooms at a love hotel are. Prices go for 2,900 to 3,900 for an hour for up to 3 adults. On the holiday night we went the baths were all in use. This is a great option for a guest from abroad who wants to experience a hot spring but doesn’t want to bathe with other people.