A 150-pound mastiff in Wisconsin woke up on New Year’s Day with an unexpected bed partner.

Waukesha nurse Lynn Sarver said she found a strange man sleeping with her massive mastiff, Benton, on a doggie bed on New Year’s morning.

“I woke up and saw someone over here on this dog bed,” Sarver told Milwaukee station WITI. She said she and her roommate “ran into the kitchen ― grabbed a knife. Then we were scared.”

The women called 911 and reported the intrusion.

“He was out. Even when I went to pull off Benton, the guy didn’t move,” Sarver told the Milwaukee Journal-Sentinel.

Arriving police officers woke the sleeping man and asked him if he knew where he was. The man said he needed his glasses.

“Once he put them on and looked around, he said, ‘Oh yeah, this is not my house,’” Sarver said.

Benton’s unexpected sleeping partner turned out to be a 21-year-old neighbor who somehow confused his home with Sarver’s and entered it through an unlocked side door, according to WISN-TV.

Police said the man was heavily intoxicated and helped get him to the right place. No charges were filed.

Meanwhile, Sarver, who got Benton for protection, is in the awkward position of defending her dog’s honor.

“My dog is pretty smart. He could probably tell this kid wasn’t a threat,” she told the Journal-Sentinel.