Jack Ledlin admits he's to blame for the death of Melbourne tradie Cameron Smith, who died after sticking up for his friend.
When Ledlin and his girlfriend called Mr Smith's former girlfriend and still good friend Natasha Stroumos a dog and a fat b**** he told her she wasn't fat, she was sexy.
The kind words to the woman he'd just shared dinner with were some of the last things he said to her.
Ledlin, now 21, pleaded guilty to manslaughter in front of a Victorian Supreme Court jury.
Prosecutors refused to accept the plea, arguing he was guilty of murder.
On Thursday the jury agreed and convicted him of the more serious charge.
After dinner on November 25, 2020 Mr Smith and Ms Stroumos had walked toward the beach at Seaford to watch the sunset together.
On the way they crossed paths again with Ledlin and his girlfriend, a short walk from the earlier incident.
A fight broke out and Mr Smith was punched in the head by another man.
He threw a punch back and in the ordeal that followed Ledlin pulled out a blade and stabbed Mr Smith once.
The blade struck his chest and pierced straight through his heart, severing his coronary artery.
It was a graze on his knee that Ms Stroumos noticed first, and then the blood coming from his chest.
Mr Smith collapsed. Despite attempts at CPR by passers-by, he died before paramedics arrived.
Two men with Ledlin and his girlfriend kicked Mr Smith to the head before all four fled on foot.
Ledlin had pleaded not guilty to murder on the basis that he didn't intend to kill or cause really serious injury to Mr Smith.
"Because you cause the death of someone doesn't mean you have a murderous intent," Ledlin's barrister told jurors.
He's due return to court for a plea hearing on charge on October 28.