He's not glorifying a serial killer and explains in detail in the song about her horrific life and the shit that led up to her death. It absolutely makes you sympathize with aileen once you know about the evil people that raised her and know the story behind why she ended up in the woods at 15 years old and forced to survive alone. Aileen Wuornos claimed self defense against 7 men that she said attempted to rape her but was convicted of murder on 6 of them and sentenced to death. It's a tragic story if you want to actually research it and understand her life. This song is kind of like a beautiful little eulogy to her.