A former Marine in Texas befriended his girlfriend's alleged rapist in order to collect video evidence of the assault, cops say.

The alleged victim, whose name has not been released, says that she visited the apartment of Elric Shawn Millner in August 2010, ABC reports. She told police Millner gave her large quantities of alcohol and when she woke up the next morning, she had no recollection of the previous night.

The next morning, however, Millner allegedly showed her videos of himself and another man forcing her to perform sexual acts while she begged them to stop. The victim, who was 17 years old at the time of the incident, can be seen vomiting and urinating on herself while Millner laughs, according to KHOU.

The teenager told no one about the incident for almost two years, KTRK reports, when she detailed the assault to her new boyfriend, who had previously served as a military police officer with the U.S. Marines. Determined to take the case to the police, the boyfriend befriended Millner in an attempt to collect the video evidence, according to the Daily Mail.

After winning Millner's trust, prosecutors say, the ex-Marine convinced Millner to show him the horrifying footage.

Whether or not the boyfriend was able to obtain a copy of the video himself is unclear. Shortly after allegedly viewing it, however, he was able to finally persuade his girlfriend to go to the police about the assault.

Millner was charged on Thursday with aggravated sexual assault and is being held on $50,000 bond. Prosecutors say they now have obtained the video and it will be used as evidence.