Every universe is like a drop of morning dew on a leaf of the cosmic tree Yggdrasil. When the cosmic twilight falls, the cosmic tree will be devoured from the root by the black hole 'Niedhogg.' When one cosmic era has ended, the next is reborn in the darkness of eternal catastrophe." Such myths are widely circulated among the cosmic, animal-like race called "Hertmi." It is said that they are the descendants of the stellar animals that once lived on Yggdrasil.

They are a race that advocates for peace and harmony with nature, and they named their planet after Yggdrasil. But Flèche is most unique among them because her wolf-like eyes symbolize terror in the mythology of the Hertemi people. Her strange appearance made her an outcast since she was a child, but Flèche's strength kept her from giving in. When a spaceship from the Cosmic Circus came to Yggdrasil, Flèche looked up to the wonderful performers.

It was as if any differences could be accepted among their ranks. So Flèche stowed away on their spaceship and began her life out in the universe. Flèche honed her archery skills in the circus and met a group of friends who sincerely accepted her. Such friendships gave her the confidence to finally leave the circus and strike out to see the universe on her own. Almost all of her belongings were stolen the very night she made that decision.

That was also the night she realized not everyone in the cosmos is friendly. In order to protect herself, Flèche grew to distrust the people around her. Over the years, she became a cunning bounty hunter, a life that came naturally with the help of her extraordinary skills. Although Flèche is no longer the innocent circus performer she once was, her bounties and ill-gotten money are often said to appear under the pillows of people in the slums just when times seem most desperate.