The protagonist is Yatsura, and she uses the setting of Yatsura in Gintama. The whole story is mainly about a hunter background. Gintama probably only appears in memories and extras. I haven't decided on the male lead yet, but he can't be more good than a knight-errant (I'm such a vulgar person).
The heroine's fighting power is off the charts and her mental problems are worrisome. Beauty is a given. If it's not normal, let the author think about it again.