"I like you, Kirihara-kun. Let's date!" Kirihara, who had just entered high school, never thought that one day someone would confess to him, so he was shocked, and that person was a very gentle, beautiful and powerful senior. It was incredible no matter how you thought about it, but the fact is that simple, the gentle senior confessed to him! Looking at the ripe kelp-kun, the gentle senior sister asked with a smile, "Kirihara-kun, are you willing?" Kirihara, who was stunned by the senior sister's smile, nodded vaguely. This is where the story about the love story of little kelp begins!