Ryō Amakusa is a sex-crazed but highly eligible bachelor with a wandering eye for women. Ichika Arima is an ordinary otaku high school girl who is close friends with Ryō's little sister Rio. Ryō and Ichika meet by chance one day, but Ryō's direct approach — asking Ichika for a kiss and a date on the same day they meet — is a complete turn-off for Ichika. Despite Ichika's disgusted reaction (or arguably because of it), Ryō is convinced that she is the one.
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