A 23-year-old Staten Island woman who became an internet sensation as part of the notorious “leash couple” has been missing since Christmas Eve, police said.

Anna Teshu was last seen about 10:30 p.m. at her mother’s Hillman Avenue home on Staten Island.

She is described as 5-foot-4 and 140 pounds. She was last seen wearing a black jacket, black shirt and black boots.

Teshu and her then-fiancé, Nathan Riely, made headlines in May 2015 when he was seen walking her around on a leash – part of what they called the BDSM activity of “puppy play,” the Staten Island Advance reported.

The woman — who referred to herself as “Xena, Nathan’s puppy” — had animal-cruelty charges tossed when she was found unfit to stand trial for leaving Riely’s German shepherd, Scout, locked up in the car they had been living in.

Scout died of heatstroke on a 91-degree day in June 2015, the paper reported.

Her lawyer, Allen Cappelli, said after her arraignment that she was “not a circus freak” and “has a series of disabilities,” including cognitive impairment.

Teshu had faced misdemeanor counts of torturing and injuring animals and confinement of companion animals in vehicles.

She told police she had locked Scout in the couple’s 1995 Mitsubishi outside her group home to accompany Riely to criminal court, where he faced a gun-possession charge.

Riely, of Fargo, North Dakota, had been arrested after police found a pistol box inside the car. He told cops that he used the loaded .45-caliber gun in the box for target practice.

Teshu told authorities that he was looking for work as a security guard. His lawyer, Joshua Benjamin, referred to him as a Marine and said the pistol had been registered in North Dakota, the Advance reported.

The charges against Teshu were dismissed in October 2015 after she was deemed mentally incompetent to stand trial. Two months later, the gun charge against Riely also was tossed.

Anyone with information on Teshu is asked to call the NYPD’s Crime Stoppers Hotline at 1-800-577-TIPS (8477). All calls are confidential.