WATCH: Sicko Sex Fiend Tells All — Graphic Content

WARNING: GRAPHIC CONTENT: Police in Fort Lauderdale, Fla., were horrified by the sickening murder of  Maria Nemeth in September 2015. The cops found a mutilated body in an apartment slathered in blood — and Maria's boyfriend Fidel Lopez trying to convince the officers that he had just discovered the body. But now interrogation footage reveals how Lopez eventually broke down — admitting Maria died during "rough sex," and finally confessing what Maria had done to make him "really, really mad!"

The initial police report by Officer Christopher Piper detailed a crime scene with "blood observed on the bathroom floor, on the walls in the hallway, and on doors." The officer added: "There were also what appeared to be several chunks of bloody tissue on the floor inside the closet." That still couldn't prepare the officers for the details of the gruesome murder allegedly provided by Lopez — before he pleaded "Not Guilty" to the crime!

WARNING: GRAPHIC DETAILS AND IMAGES: Shocking crime scene photos show the closet soaked in blood where Lopez allegedly told police he had brutally attacked Maria during sex — literally ripping out her guts through her sex organs! But first, Lopez brutally raped his lover, according to the police report!

"Fidel...began to insert several objects into Maria's vagina and rectum without her consent. Fidel advised that Maria was so drunk that she [was] unable to resist. Fidel advised that he entered a beer bottle, a flat iron for hair, and both his fist[s] into her vagina and anus. Fidel advised that his arm was inserted all the way up to his elbow...Fidel advised that he became a 'Monster.'"

But calling Lopez a "monster" might not be sufficient to explain what happened next to Maria: "Fidel admitted to pulling internal tissue out of Maria's vagina that included intestinal matter. Fidel was shown pictures of what appeared to be bloody tissue on the closet floor. Lopez admitted that he pulled and ripped the bloody tissue out from Maria's vagina and anus."

Amazingly, Lopez than called 911 — desperately imploring: "Hurry up, my girlfriend is in the bathroom! Like, I don't know man, she's not breathing! She's gonna die, man! Come on, someone help her!" That was when the police found the nightmarish crime scene.

“She called me the name of the other f**king guy," said Lopez. "And she said it twice. and she was wrong, and she was confusing me with him. At that point, I get mad. I get really, really mad.”

Lopez then tried to explain that he can't recall any details of the murder. “Yeah, man," he told police, "my mind blocks out" — adding: “I wasn’t thinking, man. I wasn’t thinking.” Lopez was later found guilty of the horrific crime, and has been sentenced to life in prison without parole.