Rumi and Naori are twins but have nothing in common, except their feelings for Jun, their next-door neighbor.

After dumping Jun, Rumi makes another request of him, one that he couldn't have seen coming.

Naori explains herself and her reasons to Jun and Rumi in order, leaving them baffled.

After seeing Mizuma's message, Jun has a decision to make about Rumi. Meanwhile, Naori is plotting something after her chess game, too.

Naori intercepts Jun at his door and asks if she can stay over at his place. And in the current, complicated situation, the Shirosaki and Jinguuji families go camping together.