According to the biochemistry student's housemate in Golgotha, Thohoyandou, the suspect always checked that their doors were locked, the Times reported.
The 24-year-old man was described by others as respectful and had been awarded with a bursary from the provincial department of agriculture.
Police set up a task team to track down the killer after four women were killed.
The man also faces one charge of attempted murder, five charges of rape, three charges of aggravated robbery and three charges of kidnapping.
University cleaner Brenda Ndove, 45, was stabbed to death last Friday and her personal items stolen, Sapa reported. Her body was found near the university's administration block.
A student, Shudufhadzo Sandy Thagisa, 20, was hospitalised after she was assaulted and robbed in May. She has since been discharged from hospital, Sapa says.
The man was found in possession of Thagisa's student identification card and cellphone.
"Also found in his possession was a cellphone belonging to the late Brenda Ndove and a hairpin belonging to another murdered woman, Livhuwani Mbodi," Masemola said.
Mbodi, 22, was found dead on the university's premises in March.
"Like the discovery which was made when the body of Ndove was recovered, Mbodi's head also had a deep wound at the back, with other wounds on her back, seemingly caused by the act of pulling her from the original scene of crime to the dumping place," Masemola said.
Investigations revealed Mbodi was raped before she was murdered.