Demon Time

A reference to Japanese animated media portraying a character unleashing their true potential for a (often) limited amount of time before they revert back to their regular state. The timeframe in which the character can persist in this elevated state is known as Demon Time, and is often used in reality as well to express extreme bursts of passion.

Eg 1: The Hero was getting destroyed by the Bad Guy, but then he went full demon time and took the win!

Eg 2: John goes demon time in the gym. I can’t keep up with him when we work out together!