Karoline Heintz, an 18-year-old incoming freshman on the Pennsylvania Western University women's soccer team, was allegedly stabbed to death by her boyfriend, 18-year-old Royce Moser, according to court documents. Moser reportedly told investigators that a "demon" had taken over him during the attack, while his mother is accused of helping to cover up the killing afterwards. The case has drawn wide attention given Heintz's youth and the unusual nature of the defence being described.

Heintz was due to begin her freshman year as a member of the university's soccer programme when she was killed. Moser is in custody facing charges over her death, and his mother faces separate allegations of assisting him following the alleged stabbing, though further details of the charges and the circumstances leading up to the killing have not yet been fully disclosed.