Rasen Kaidan

An adventure game that specializes in bukkake. Progress in the game by doing perverted things with the heroine and two other people who are staying at the ryokan together, all while idly spending ordinary days at a ryokan.
Whilst in the setting of the ryokan, the more mysterious you can make your perverted doings, the more money you can receive. With that money you can purchase different sex play items or items that can boost your stamina and so on.

[From DLsite English]