Makoto, the protagonist, was sent to stay with his cousin Minoru during summer vacation while his parents went on a honeymoon.
One day, he discovered that Minoru was a manyokko—someone with magical abilities.

"So you’re… one of those ‘gifted’ people too, huh?"

As it turned out, Makoto himself also harbored strong magical potential.
He became acquainted with Minoru’s friend, Kyou, and for a while, it seemed like his days would be filled with joy.
But then, one day, Minoru suddenly stopped coming home.

To find him, Makoto and Kyou decided to visit Natsuki at the Kanda Dojo.
There, they met a boy named Chisato, who admired Kyou but seemed to have a competitive streak toward Natsuki.
Through casual conversation, Makoto and Chisato quickly became friends.

As they talked, Makoto sensed that Chisato also possessed extraordinary magical power.
Meanwhile, Kyou managed to track down Minoru, but something was off… Minoru transformed and attacked.
Facing Minoru, Kyou struggled to fight back and was drained of so much magical energy that he couldn’t even maintain his transformation.
Seeing Kyou in such a state, Chisato blurted out,

"I’ll fight in your place! For… for Kyou’s sake!"

Makoto was struck by Chisato’s determination and wished he could muster that kind of courage himself.
Just then, he faintly heard someone calling out. Following the voice, he arrived at a place where…

"Mugyuu! That hurts! Don’t step on me, kero!"

There sat a plump, talking frog named Kaerotta.
Kaerotta explained that its contract with Minoru had been forcibly broken. After sizing up Makoto, it said,

"Hey, kid, wanna make a contract with me, kero?"

Meanwhile, in the shadows Shion watched the manyokko with a suspicious gaze. What were his intentions…?

A new, turbulent tale of manyokko was about to begin.

[Translated from dlsite]