Bohling then carried on with the sexual assault, before strangling Ms Liu with a belt, while filming the act.
Interrupted by a pair of hikers who stumbled on the crime, he pushed the rape victim over the same ledge while she was unconscious.
The 21-year-old landed at the bottom of the slope next to her friend, who called the emergency services, telling them her friend was “gasping”.
Both women were found by rescue workers at the bottom of the ravine.
The rape victim was seriously injured and taken by helicopter to hospital, where she died later that night from her injuries.
Ms Chang, whose fall was broken by a tree, somehow survived.
Bohling, who had been staying at a boarding house in the nearby town of Oberstor was arrested after a massive police operation involving 25 emergency vehicles.
He initially refused to talk to the police, but later made a statement to the investigating judge before being remanded in custody.
His lawyer told the court Bohling “was aware that the victim could die without help, yet he still left her behind”.