The jury was told that Herring was convicted of coercive and controlling behaviour against the teenager following a previous trial.
Prosecutor Jamie Scott said the accused had isolated the victim from her family, inspected her phone, assaulted her and previously locked her in his bedroom.
The teenager was airlifted to hospital, required a blood transfusion and assistance to breathe.
When questioned by police if her black eyes were new, Herring replied “no, she’s had them for two or three days.”
Her left lung had collapsed and she sustained multiple fractures around her ribs, pelvis and spinal bones.
The prosecutor said the defendant claimed they “got into an argument about cheating.”
Mr Herring claimed the victim threatened “I’ll jump out the window, then”, and said he tried to grab her before she “leant to the side then dropped herself out the window”, the court heard.
The trial continues.