It's the second semester and it's almost time for the school festival, "Hakuhou Festival". Yuuto's class activity representatives are Shiina and Yuuto, and their class decides to host a Cosplay Cafe. Haruka is a little jealous because Yuuto is always with Shiina, working on the festival. It's then that Haruka is asked for advice on how to make a cosplay costume by Yuuto. Yuuto learns from Haruka about a cosplay specialty shop in Akiba, and asks her if she'd come with him on the upcoming Sunday. Haruka, of course delighted by Yuuto's invitation, did not see any reason to refuse. However, she had already made other plans for that day and...