My thought process was to bring a twist to a character that I like very much. Inspired on Noir style, playing with black shapes with a very solid style.
The longer hair always looked extra etherial and spooky to me in media, but Danny Phantom isn't just a Phantom, he is a hero, and I mixed the "Bat-signal" design with the "Gotcha!" feeling when you turn-on a flashlight into a night creature, making them confused and curious, backtracking on their step, or being interrupted in the middle of it.