Livingston was arrested at the home he rented with his girlfriend, and is suspected of killing her aunt who was staying at the home late Friday night.
Livingston also faces charges of attempted murder for allegedly attacking his girlfriend. She appeared to have severe bruises on her face and was treated and released from the hospital. The killings happened sometime after 11 p.m. on Friday, and police say Livingston had just gotten out of jail a few hours before the murders.
Friends told KOMO 4 News that Livingston was arrested and jailed Thursday for severely beating the man he's now accused of killing.
Friends say Andrew "AJ" Geissler, one of the victims, was a sweet person and always had a smile and warm heart.
"Andrew will get justice for this. He will not be silenced," she said.
"I could never imagine in a million years this could happen. That they could let this man out of jail after what he did in the first place," said Rhea Love, who had visited the home earlier Friday before Livingston returned.
She and a neighbor say Livingston suspected his girlfriend and the murder victim were becoming romantically involved. Love believes that is what triggered the attack inside the home on the corner of South 19th Street and South L. Street.
"AJ kind of kissed her and everything like that. Aaron saw," O'Leary said.
Love described Thursday's beating, saying her friend suffered severe facial wounds, including a broken eye-socket, at the hands of Livingston. A neighbor remembers seeing the male victim bleeding, stumbling down the street next to the home, and an angry Livingston outside nearby.
Love is shocked that Livingston was released from custody. She and the girlfriend thought he would be held until at least Tuesday.
"She was like, 'They let Aaron out of jail. I can't believe it.' I said I can't believe it either. She thought she had more time to go get a restraining order," she said.
O'Leary said the situation is tragic and preventable, despite the passion that can bring about violence.
"No one deserves to get killed over a kiss," O'Leary said.