Maiden Machine Assault VI Dark Master -Climax Training- Extreme Motion - 01-Torte - Adult Sex Game

Souta is a regular school on a class trip to Kyoto
During the trip, he sees his classmate Mana being dragged away by a mysterious robot.
Following it, he arrives at a strange and unknown place, and sees something he shouldn't have...
Finally, he finds out the secret of the mysterious girl Erika and her master.