Here's a breakdown:
* Straight scene hair is a hairstyle popular in the early 2000s scene/emo subculture. It typically features long, straight hair that is often styled with side-swept bangs and layers. The hair is often dyed in dark colors like black, brown, or dark red.
* A mullet is a hairstyle that is short on the sides and back, but long in the back, often with a distinct horizontal separation between the short and long sections.
While both styles can be considered "alternative", they are distinct and easily distinguishable from each other.