Fei Rune appears in the anime Inazuma Eleven: Chōjigen Dream Match as a midfielder for the Inazuma Battle Eleven team. Within this special match, his role is primarily supportive, demonstrating his field vision and passing ability by successfully delivering the ball to teammate Hakuryuu, who then scores the first goal for their team using the technique White Hurricane. During the events of this match, Fei does not use any hissatsu techniques of his own.

While the Dream Match offers a limited glimpse of his on-field abilities, Fei Rune is originally established as a main character throughout the Inazuma Eleven GO Chrono Stone series. His background is marked by a painful childhood; he was abandoned by his father as a young child due to his nature as a Second Stage Children, a group of evolved humans from the future. His father left behind a plush rabbit toy as a gift, but Fei came to resent this object and eventually threw it away in anger. This resentment later caused him to hesitate to use his keshin, a spiritual avatar, because it bore a strong resemblance to that same rabbit toy. He was eventually convinced to overcome this reluctance by Nanobana Kinako.

Fei was originally a member of the organization Feida alongside another individual named SARU. To execute a specific plan, SARU erased Fei's memories and sent him back two hundred years into the past. With his memories of his true origins and his involvement with the Second Stage Children removed, only his pure, genuine love for soccer remained. This memory loss allowed him to play a key role in helping to protect the sport from being erased from history.

His personality is generally cheerful and he is shown to be naturally helpful towards others. He possesses a caring nature and is perceptive of the feelings of those around him, such as when he notices sadness in his friend Matsukaze Tenma. His actions are ultimately driven by a belief that there are many people in the future who share his passion for soccer, which fuels his desire to protect the sport.