Annie Kennedy, 30, attacked Francis Berry at her flat in Kremlin Drive, Stoneycroft, on May 16, 2013.
The drug addict claimed she acted in self defence, suggesting her victim had tried to indecently assault her.
But a jury at Liverpool Crown Court convicted the mum-of-two of manslaughter, after finding her not guilty of murder.
Kennedy, now of Knighton Road, Walton, had admitted to “prodding” Mr Berry in the chest with an orange-handled screwdriver.
However, the victim also had a wound to his groin, which she denied causing, and later died from a flesh-eating infection related to that injury.
The court heard Kennedy lied to police when they arrived on the scene, telling them Mr Berry was her uncle, and that he had molested her when she was younger.
She later accepted he was not her uncle, but said she had been frightened she might be sexually assaulted, having been abused in the past.
Mr Justice Edis said he was prepared to accept that Mr Berry, who had been drinking, may have acted in a sexually provocative manner.
But he said nothing that the victim did justified how Kennedy reacted, especially as she was accompanied at the time by another man, Darren Jackson.
Sentencing, the judge said: “There was no need or justification to take up a weapon.”
During the nine-day trial, the jury heard police were first called to the victim’s home at around 7.20am on May 16.
It was Kennedy who dialled 999, after finding blood on the floor of Mr Berry’s empty flat in Osborne Road, Tuebrook.
Officers found another flat open upstairs, with more blood and a knife under a bed.
A search of Mr Berry’s mobile phone revealed that a call had been made to police the night before.
Mr Berry arrived and said he had helped a neighbour who had suffered a cut to his hand.
Officers then drove him and Kennedy back to the defendant’s flat in Stoneycroft.
A resident who lived there called police at around midday, after being alerted to an incident by Mr Jackson.
He saw Jackson hide a black-handled screwdriver thrown to him by Kennedy, which was considered by experts to have been the weapon that caused the fatal blow.
The 37-year-old, of Merton Road, Bootle, pleaded guilty to perverting the course of justice and was jailed for nine months.
