A Casper man pleaded not guilty to charges alleging he sexually assaulted a woman as she slept in May.

Luke Evans appeared in Natrona County District Court Tuesday morning and pleaded not guilty to a single count of third-degree sexual assault.

If he is convicted, Evans could face up to 15 years behind bars.

An affidavit of probable cause alleges that Evans went to the victim and her roommate's home on May 9. The alleged victim's roommate was in an on-and-off relationship with Evans.

At some point, according to the affidavit, the alleged victim's roommate told Evans he could sleep on their couch because he was too drunk to drive. Instead, Evans allegedly went into the victim's room who let Evans sleep in her bed because she felt sorry for him, court documents say.

The victim fell asleep and later woke up to find she was no longer wearing any clothing below the waist, the affidavit alleges. Court documents say Evans told the alleged victim, "you were out cold," after the incident.

A DNA test taken during the alleged victim's sexual assault examination showed a "strong match" between her and Evans.

A potential trial in the case is should take place in late November.