After years of being bullied by his arrogant home tutor sisters, Masato acquires a mysterious hypnosis device that allows him to control the minds and bodies of others. He tests the device on the haughty Serina, breaking her will through forced pleasure and absolute obedience. Now completely under his thumb, a corrupted Serina is coerced into helping Masato target her sister, Haruna.
Maa-kun deepens his hypnotic control over Haruna, manipulating her into believing that sexual acts are essential parts of her tutoring lessons. After breaking her resistance and forcing her into a submissive maid role, he turns his attention to Serina. By leveraging Haruna's brainwashed state and his own hypnotic powers, Maa-kun forces both sisters into a state of absolute obedience, culminating in a depraved threesome where they are reduced to mere slaves of pleasure.