She also has a beautiful brown wig done up in a ponytail.
Quiet herself is a highly trained sniper and honestly with that explanation, I don't know if I can come up with a reasonable reason as to why she's dressed this way.
I kept on playing videogames the first ones were Spyro, Crash Bandicoot, Final Fantasy and Tomb Raider for me , reading comics and listening to the music I liked.
Be sure to check out Meryl Sama's Patreon for more of her work and other links! The scenery is all outdoors in very forest like areas.