The word used to describe a person(s) with a glittery/sparkly moustache and/or any other type of light reflecting facial hair etc. Glitterstache can also be used as a way to describe someone with sequins, beads or any other type of sparkly facial hair.
The word glitterstache can also be used as an insult. For example...
"OMG! Heather is such a glitterstache."
Lastly, the word can also be used to replace any other word. For example...
"It looks so pretty! It has such poise, elegance and glitterstache."
Or...
"Eh! You know sometimes I just feel so glitterstache."

Literally everyone, ever. Including the writer of this definition.