Founded in 1977 by sisters Tish and Snooky Bellomo, Manic Panic is an alternative beauty brand from New York City rooted in punk and self-expression culture.  The company is best known for its semi-permanent fantasy hair dyes (Classic High Voltage + Amplified), as well as bleach kits, color conditioners, and color-care basics. 
The brand focuses on "Color With A Conscience™" positioning and formulas that are 100% vegan and not tested on animals. 
People love it because it has bold colors that mix well. It usually lasts about 4 to 6 weeks, depending on how often you use it.