Mature Content Description

The developers describe the content like this:

all characters are over 18 years old.
The game contains nude pictures of characters and nude pictures of public scenes.
Please note that the content of the image may involve involuntary sex.

About This Content

The story takes place in a masquerade party, where you can communicate with the characters in the party and attack female characters through mini-games. By exploring and solving puzzles, you can learn more about the organization behind the gathering, and uncover the background story of religion in the lunar mirror game.

The game is the background of the Cthulhu horror story, which can bring you a tense and exciting experience.
As a derivative work of "lunar mirror", the game inherits its gameplay
You can use the A or D keys to move the character left and right to explore. Solve puzzles and advance the plot by collecting clues and props.
This DLC contains adult-only nudity for female characters in the game