Konatsu is about to start a new school in a new town, and she's basically all on her own. Her dad just got a job overseas, and her aunt can only check in from time to time. It's a lot for a shy, reserved girl to handle. But on one of the first days of class, she discovers that the school has an aquarium The club that runs the aquarium is headed by an older student named Koyuki, and Konatsu is instantly drawn to her. Konatsu's introverted tendencies are hard to overcome, but maybe she's found something worth coming out of her shell for?

From the moment they met at the Aquarium Club's open house, Konatsu has admired Koyuki and treated her like she wasn't a distant figure on a pedestal. In turn, Koyuki has been open and welcoming to the new girl who stirs her heart. When the time comes to pick a club, Konatsu chooses the Aquarium Club with Koyuki. And even though it's just the two of them, they manage to host a successful open house. What's next for Koyuki and Konatsu, now that the shared experience has deepened the bond between them?