SSNI-314 Special Mission Investigator Okuda Saki, who was raped while restrained and fell into pleasure

I am a member of the secret 'underground public security organization' formed to eradicate crimes in the underworld... This organization, while capable of conducting extrajudicial investigations, is literally an 'underground organization' that the state does not officially recognize, so operational failures are not permitted. Half a year ago, I was in charge of investigating a gang rape incident and had the mission to uncover the entire picture of the criminal group behind it. Then, I successfully tailed one member of the perpetrator group and made my way to the core of the organization's hideout...