At the beginning of the story, a girl accidentally traveled through time, so she began to conquer the heroine, and slowly fell in love with her on the way; at the end of the story, the two girls accompanied each other, walking towards a new edge, and they were inseparable from now on.
(Sorry for the bad writing! I am original and accidentally plagiarized.)
(The female protagonists (attackers) in different planes are all the same person.)
Concept: Lily