A family-run hot spring inn famous for its hidden hot springs deep in the mountains. However, both parents died in an accident. The four sisters decided to take over the inn, which was also a memento of their parents. But they had no ability to run the inn and were on the brink of bankruptcy. However, they used their proud giant breasts to successfully revive the inn in Project SEX story.
※There are no performers under 18 years old in this work.
