"I must protect 'my other self'."

100 years into the future.
On Earth, 40 years had passed since the discovery of "Multi Universes". In Tokyo, humanity, science and technology had advanced smoothly.

As a bounty hunter, Tomoe chased down criminals for a living.
However, in the midst of trying to exterminate a cult, she had let a criminal get away.

Few days later, Kira Seishirou told Tomoe:

"Your other self on another Earth is being targeted."

Seishirou worked for the Relocation for Public Safety Bureau
and had sought her assistance in trying to exterminate the cult once again. Confused but needing to protect her own life, Tomoe set foot on the universal transfer device, and...

[Translation of official website story summary.]