Astraea is a character from the anime series 'Sora no Otoshimono,' also known as 'Heaven's Lost Property.' She is an Angeloid, a type of advanced robotic being, specifically a 'Type Delta' and is known for her immense physical strength and combat abilities. Astraea is portrayed as a somewhat airheaded and naive character who struggles with academic tasks but excels in physical combat. Despite her initial mission to eliminate Tomoki, the main protagonist, she eventually becomes one of his friends and is seen as a comedic yet endearing character throughout the series.