On the morning of May 12th, sixteen-year-old Tomoyo wakes up with a pelican eel tethered to her spine. That same morning, three bodies turn up in the area. Her childhood friend Raika has been missing for three days. And the sky... why isn't anyone talking about the fact that it's gone?

When Tomoyo's phone finally buzzes with a message from Raika's number - "Come to the aquarium. Now." - she goes.

What she finds there is only the beginning. The eel on her back knows what happened to those bodies. It knows why the sky disappeared. It knows what May 12th really means.

It just doesn't want Tomoyo to remember.