College student Yuno is fascinated by murder scenes in suspense dramas and begins searching for a club that matches her interests, eventually crossing paths with Chinami. Chinami is an eccentric girl who secretly researches choking and asphyxiation play alone, and out of loneliness, she invites Yuno to join her. Though hesitant at first, Yuno agrees to participate. What follows is an extreme exploration of choking and breath control, where she experiences the sensation of stopped breathing and lost consciousness. Using various techniques, she is comfortably strangled, drifting in and out of awareness while occasionally receiving sexual stimulation to examine psychological responses. Through their fulfilling club activities, their bond deepens as they immerse themselves in the world of breathplay fetish.