Hint 21: The kid culprit is Battler

Hmph. Even in my games, Battler culprit theories were some of the most popular, weren't they?
It seems so. Sheesh, why does everyone think I did it?
If you're a culprit, that automatically makes your parents culprits, too. There's no need to worry any more. We've already won.
There's no need for any more discussions or hints. Let's move ahead with the answer!
Is it over?
Well done. It seems a mystery of this level wasn't enough to beat those two after all.