A British backpacker, one of two people left dead after what is believed to be a murder-suicide, wrote of her intentions to travel the globe shortly before her body was found in an inner-city Sydney apartment.

Police are investigating the deaths of 22-year-old Amelia Blake and her Nepalese boyfriend, Brazil Gurung, in Newtown on Friday night.

Emergency services were called to a unit on King Street about 5:30pm on Friday, following concerns for the welfare of a man and woman.

Police attended the unit, which sits above a Persian restaurant, and discovered the bodies of Ms Blake and 30-year-old Mr Gurung.

The two were believed to have been in a relationship for about a month.

NSW Police officers examine the scene where two people were found dead on Friday. ( Supplied )

Following the discovery by police, friends of Ms Blake took to social media to share their grief.

"Amelia was a beautiful young woman and an amazing life-long friend who I'll miss for the rest of my life," Rhys Collington wrote.

Shortly before her death, Ms Blake wrote on social media about her intentions to travel the world.

"I see my path, but I don't know where it leads," Ms Blake wrote on Instagram.

"Not knowing where I'm going is what inspires me to travel it."

A former employer described 30-year-old Brazil Gurung as a "model employee". ( Facebook )

Mr Gurung was employed at the Fogo Brazilia Churrasco restaurant as a chef for two years before resigning about a month ago.

Restauarant owner Ian Dresner said staff were in shock after hearing the news about their former colleague.

Mr Dresner described Mr Gurung as a "model employee" who "worked hard, worked long hours" and was polite.

NSW Police said post-mortem examinations were conducted on the two bodies and would form part of the brief to the coroner.

Police have establised Strike Force Tenisonwood, with officers from the Newtown Local Area Command and the State Crime Command's Homicide Squad set to investigate the circumstances surrounding the incident.

Detectives have asked anyone with information to come forward.