A monster tortured his girlfriend and her baby daughter in a Brooklyn basement for three hellish months — repeatedly raping the woman while denying them food and bathroom use, sources told The Post.

A sadistic Yohannes Anglin, 33, allegedly burned his 27-year-old gal pal with cigarettes and slashed both her and her 2-year-old daughter from another man, the sources said.

The nightmare took place in a three-story rooming house on Schenck Avenue in East New York from Feb. 23 to May 29, when the woman’s screams were finally heard by a good Samaritan, who called police.

“The guy who called 911 said that the beating was so severe, it sounded like she was getting murdered,” said one horrified tenant.

Deyrel Knights, who made the 911 call, was with cops when they first entered the torture chamber.

“She couldn’t speak because her jaw looked like it was broken,” Knights said.

“And then we saw the little baby. She looked like a skeleton.”

Cops found the woman tied to the bed, and Anglin was arrested at the scene. He was charged with kidnapping, rape and assault, and held without bail.

Neighbor Cleavon Aikins said the dungeon “was a mess, as if a tornado hit it. It was nasty.”

Anglin and his girlfriend lived in the building for a month before the relationship soured.

He allegedly bound the hands and feet of his victims with duct tape — at one point tying the woman to a bed and raping her.

He struck them with the back of a knife, inflicting bruises and several gashes, authorities said.

The victims, who remained hospitalized yesterday, were banned from using the bathroom — and forced to urinate in bottles.

Additional reporting by C.J. Sullivan