Honkai: Meet Her in Honkai

[Single heroine Kiana + non-invincible + early daily life + no system + local protagonist] "Big bad guy, tell me, how can we completely eliminate Honkai?" The girl asked the boy a question. "Huh? Well, it's hard to say. So far, many people have sacrificed everything for this goal, but Honkai still shows no signs of dying out." "Then tell me, can we really do it?" "Oh, I didn't expect you to ask such a question?" "What are you doing? I'm asking you seriously." "Then let me answer a little more seriously. No matter what, I will definitely continue to fight Honkai until the last moment between me and it." This is his and her story, everything started from their meeting. They met because of the collapse, but also—— Parting due to collapse.