Prosekaigender

 is a xenogender and fictigender connected or related to the game Hatsune Miku: Colorful Stage!, also known as Project SEKAI. This gender may be related to a character(s), group, location, or song within the game, or the game in general.

Etymology
The term uses the word "Prosekai", a common shortening of Project SEKAI, and the suffix "-gender"

History
Prosekaigender was coined by Tumblr user dogboyposting on his sideblog Radweekend on March 13th, 2021 alongside its subsets.

Subsets

 * Virtualsingroupic
 * Vivibadsquadgroupic
 * Leoneedgroupic
 * Momojumpgroupic
 * Wonderxshowgroupic
 * 25nightcordgroupic

Flags
The flag for prosekaigender was created at the time of the term's coining, each flag represents a group within the game, using the groups color within the game.

The stripes in order, with meaning are listed below Teal represents the VIRTUAL SINGER group, green represents MORE MORE JUMP!, blue represents Leo/Need, Purple represents Nightcord at 25:00, Pink represents Vivid BAD SQUAD, and orange represents Wonderlands x Showtime. The symbol for the flag is that game's logo