SINGAPORE - A 43-year-old woman who assaulted her live-in boyfriend and stomped him to death after a quarrel was on Thursday (March 16) sentenced to 5½ years' jail for culpable homicide.

Sukanya Praphuttha, a Thai national who is a permanent resident here, pleaded guilty to killing 55-year-old handyman Lee Yang Boo by using her right foot to stomp the left side of his head at their North Bridge Road flat.

The High Court heard that sometime during the assault in the early hours of March 1, 2015, a neighbour heard the Singaporean man - who was 10kg lighter than his girlfriend - shouting "don't beat me" and "stop beating me".

Praphuttha and Mr Lee had lived together at the rented flat for seven years and had a tumultous relationship, marked often with quarrels and, at times, physical fights.

On the night of Feb 28, 2015, the couple went drinking with friends at a nightclub. There, Mr Lee scolded Praphuttha for dancing with a male stranger.

Back at home, after more drinks, the couple quarrelled after Mr Lee accused Praphuttha of having a sexual relationship with the stranger in the club. But she eventually placated him and put him to bed.

Later, Mr Lee suddenly woke up and continued to hurl vulgarities at Praphuttha and her parents. A scuffle ensued which resulted in Mr Lee laying down on his side on the floor of the bedroom.

As he lay on the floor, Praphuttha stomped on his head with such force that he suffered skull fractures. She claimed that she lost her temper when he continued to hurl vulgarities at her, so she hit him repeatedly on his face, body and limbs.

As she helped Mr Lee onto the bed, she noticed that his left ear was bleeding and he was having breathing difficulties. At about 4.30am, she sought help from a neighbour, who called the police.

Mr Lee was pronounced dead at Tan Tock Seng Hospital at about 6.45am. An autopsy concluded that he died from a head injury. A total of 47 bruises were found all over his body.

A medical examination of Praphuttha found a handful of bruises and abrasions.

She was initially charged with murder but the charge was reduced to culpable homicide, which carries a maximum of 10 years' jail.

Deputy Public Prosecutor Mohamed Faizal sought six years' jail, arguing that Praphuttha had attacked Mr Lee when he was already "down for the count". Mr Lee died a slow and painful death, he said.

Praphuttha's lawyer, Ms Cheryl Ng, argued that she was triggered to act when Mr Lee insulted her parents.