A German woman cops are calling “sex-crazed“ is going on trial for dismembering her boyfriend using a circular saw - while he was still alive.

Known only as Gabriele P., the 31-year-old allegedly wanted to end her relationship with the victim, known as Alexander H.

“She wanted to be rid of him,” prosecutor Thomas Steinkraus-Koch said, according to the U.K.’s Daily Star. “We assume the man was in a state where he could not defend himself and where he could not know that he would be killed with a circular saw.”

He added: “The accused has given information enhancing the action sequence of events that lead us to believe what happened wasn’t an accident.”

According to the prosecution, the accused killer and Alexander lived in a house she inherited from her grandmother.

Locals called it the “Hippy House” and the pair were known for throwing raucous orgies.

Cops say it was the aspiring teacher who instigated the wild group-sex action.

But then Gabriele fell in love with a man named Christian K., 33, and wanted to torpedo the relationship with Alexander, her partner of nine years.

And in May 2009, cops say “the relationship ended in a bloodbath.”

The woman then reportedly used the saw to tear open his chest, while he was still alive, and decapitate him.

Gabriele then allegedly wrapped the body parts in plastic and with the help of her new beau and buried them in her garden.

Shortly after the alleged murder police believe Gabriele called Alexander’s mother, sobbing he had run off to Romania with another woman.

Years later, Christian revealed the horrific truth about what happened to Alexander and someone told the cops.

Her lawyer claims Gabriele was desperate: “The relationship was very difficult. My client could not see any way out.”