Firegender is a xenogender that is in a constant state of change that never truly extinguishes. It is aesthetically linked to fire as a visual metaphor or symbol.
History
Firegender was coined on or before July 26, 2014 by Tumblr user deanwinchesterinmyheart.[1]
Flag
The flag was created on or before August 29, 2015 by Pride-Flags on DeviantArt.[2]