Mark is quiet, calm, shy and smart.

Cassidy, on the other hand, is a lot more excitable and... loud.

Nonetheless, despite their differences, they are best friends.

But then something peculiar happens.

Something that turns their worlds upside-down.

Something that changes their lives forever...

Update from 2020: ah
I do not own the image used in this cover. It's a screenshot of the Inazuma Eleven anime of Hiroto/Xavier and Midorikawa/Jordan.