サマヨイ淫夢校舎～こんなHな授業、ありえないっ！～

One day, Umi, Mitsuko, and Akane obtain an old notebook containing lewd fantasies of boys. However, when they get the notebook, strange things start happening every day after school. The things written in the notebook become reality, and the once peaceful school becomes full of sexual desire, with boys demanding lewd acts as if it were normal. Is it a dream or a curse, and is there any way to escape? The girls fight against the debauchery while trying to find clues to escape this dreamlike, blurred world between reality and fantasy.