What is the definition of Forbidden Fear?

A 'forbidden fear' is like a secret that you're so terrified to share, even with the person who's supposed to be your best friend, but you can't quite put your finger on why it's so dreadful. It's the fear of the dark, the monsters under your bed, or even the idea of failing to impress someone you're smitten with, because the thought of it makes your heart skip a beat like a kazoo at a concert.

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Here's an edgy sentence: "Despite my terrifyingly well-prepared 'I won't tell' speech, the forbidden fear of the clown's scarier than the ghosts in the attic."