Multifour is a term that refers to someone who is multigender, multisexual and/or m-spec in general, multipronominal, and multinominal. One's name, pronouns, gender, and orientation be fluid or static, situational or non-situational, etc. As long as one's labels and identity fall under the umbrella of all of these terms, they may use it.
Similar terms include Fluid-fluid-fluid, a combination term for name/pronoun/and genderfluid individuals.
History and Flag
"Multifour" was coined by fandom user johnnienotjohnny on June 19, 2021. The flag was made the same day, combining a few of the the colors from the multigender, multisexual, multipronominal, and multinominal flag following the diagonal tilt of the multipronominal flag.
The alternate flag was created with the same colors except tinted pink, and a few additional shades of those colors too (both of which are purely an aesthetic choice). The stripes are lined up in the typical pride flag format of horizantal lines.