What awaited was a grand and cruel 'trap' set to corner Koharu. The bonds of rope, eroding reason! Fall into ecstasy! The female detective Koharu, invincible against both gunfire and hand-to-hand combat, dubbed the 'strongest,' finally relaxes her heart with love for a certain young man. However, that happiness crumbles when his girlfriend is kidnapped by the criminal organization 'Black Dog.' Small spring infiltrates alone and gets captured, undergoing extreme brainwashing. But she escapes at an opportune moment. In the instant he saves his girlfriend with his life on the line, her boyfriend reveals his true identity...
