My theory is that Black (A villain from a famous serie abbreviated DBZ) is the lost uncle of Betty.
This is comprobed?
Hummm... Yes.
Why?
Because like you are watched the episode "Do or Die", her hair turns into pink when use the Rabdophobia.
What inspired me?
When I watched the animation livestream of this episode in Youtube and Cami animated Rabdophobia in the Gaster's Battle, an commented in the Live Chat "Is a Super Saiyan Rose!".
And in this Comic Page, Frisk discover this theory.
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