look up any word, like cunt:
A day in which anime fans all watch the same exact anime episode of a anime on the same exact site.Most of the time on Sejun Day the anime fans crash the site due to MAJOR traffic!This term was made by Jared Nguyen and Joseph Whang.
-AnimeJunk.com crashes due to huge traffic!-
Senjun Day People:Sucess.
by Ethan Hong Long Nguyen September 20, 2012