Do you have to change characters every time they're unlocked, or can you just do the entire run as, say, pumpkin, unlocking every character and all 6 runes, all without restarting?
I am unfortunately not the one who made the categories. No one was reviewing runs for this game when I entered my times. I had to ask to become moderator because I could not get a response from the sole moderator Gamefreak2350 at the time for about a month. However, I assume you can stay whatever character you want. The two times posted currently in 100% show them not restarting after they pick up the witch character, so I assume it is personal preference.
As long as I see you pick up all three characters and all six runes in game and finishing with them in your possession when you defeat the final boss I am fine with calling that 100%.