Imouto wa Gal Kawaii

Everything changes overnight for Shouhei Shindo when his father remarries. Suddenly, he finds himself living under the same roof with a new stepsister—his classmate Rino Mizusawa. Rino is a full-on gal: bold, fashionable, blonde, and known for her uninhibited personality. As an introverted otaku, Shouhei assumes they belong in completely different worlds and worries that living with a gal will be an impossible challenge.

To his surprise, Rino treats him with warm, unfiltered affection and seems completely unbothered by her provocative habits around the house, frequently wandering around in revealing outfits or just a bath towel. The awkward tension begins to melt away when Shouhei discovers that beneath her flashy gal exterior, Rino secretly shares the exact same otaku hobbies as him.

As their shared secrets draw them closer, the line between step-siblings and lovers blurs. What starts as innocent banter rapidly escalates into undeniable temptation, plunging the two into an intense, secret relationship hidden behind closed doors…