@Surfa the practical outfit for her fighting style is light and flexible with full degree of movement, even more so than assassin types. Think of it like an agility based fighter that uses her legs, sabers, and large swinging slashes that basically make her body spin like a top -.- Loose fitting clothes with full mobility around the joints; there can't be any stretching when they fold their body in half both front and back, do splits, etc. Her clothes are kind of accurate as far as type... design choice... eeehhhhh. 
...because ✨MAGIC✨