Have multiple story start types, not a prefix.
Examples:
In Tanjiro's story, he arrives home and sees his family dead, but let's say that some random oni other than Muzan is still there. His mission will be to kill the oni. It doesn't even sound like the story of a game out there lol
In the story of Obanai he was a slave to an oni serpent. At one point he was going to be given as a sacrifice but the pillar of flame saved him. Let's say you had to dodge enemy acts while the Pillar of Flame Save you.
Etc 