I see a 100% category, but nothing has been defined for it yet. Is it just a placeholder for now?

Honestly I've never ran it, but it'd be playing the game as hello kitty and getting all the collectables (videos, friends, costumes, weapons, etc.) + unlocking bad batz maru. But because some of the unlockables you have to unlock as bad batz maru, you have to play the game twice, once as hello kitty, and another as bad batz maru.

Sorry to reply to such an old post but I had a question about 100% and figured this would be fine. A potential new runner approached me about it, asking how it'd work exactly. But honestly, I'm curious. Do the unlockable clothes for Kitty come in a random order from random levels or is it consistent? Also playing as Badtz unlocks some too so wouldn't you have to switch back to Kitty to verify that you have them? And then lastly, when playing as Badtz don't you have to repurchase all of the character info and videos and etc even if you got them as Kitty? There's so many confusing variables to me, I apologize.

Heyo, so I've never done 100% personally but I'm pretty sure everything is consistent. For example for the Bonus Sailor Costumes you have to complete a level with an S rank. You can look up how to do these things on sites like gamefaqs and others who have a list of unlockables and how to get them (https://gamefaqs.gamespot.com/gamecube/927518-hello-kitty-roller-rescue/cheats). Not 100% sure if the videos stayed unlocked or not, I guess if not you'd want to first beat the game as Hello Kitty then go through the game as Bad Badtz Maru and unlock everything with him instead of Hello Kitty, so you could have all the videos and unlockables. Since one of the unlockables is beating the game as Badtz Maru.

Hope that makes sense, again I haven't done the category personally but I had the idea of doing it before so created the category if anyone wanted to try. Also if your friend ever wants to hit me up on twitter or anything, I'm always down to talk about stuff.