Suffer with a smile!!! Otoha Neiro, a pure girl who used to be active as an underground idol, takes to the stage in the egoistic deep throating production "Smiling Mouth Toilet," which forces her to endure with a smile no matter how her throat is violated. The dazzlingly pretty girl's expression becomes distorted as her pure white throat is tortured, but because she is a masochist, her precious jewels continue to flow from Hitomi... She accepts such subtle torture as pleasure, and even in the midst of chaos, she continues to smile and suck the meat stick, going wild with joy. What we catch a glimpse of beyond this decadence is the figure of Neiro, who has been reduced to a "smiling mouth urinal," who continues to smile even when her throat is violated by a man's penis...