Sam Fleming accused his girlfriend – who lived in Bury – of cheating on him which she denied.
At Manchester Minshull Street Court, Joshua Bowker, prosecuting, said the pair were friends since childhood, but then started a relationship in early summer 2019.
"Despite early positive signs, a short while into the relationship things turned unpleasant", Mr Bowker said.
On a Saturday morning in August, the defendant accused her partner of cheating on him, which she denied.
He called her an "array of vulgar names", the court heard.
The woman then left the property and went to her mother's home.
The defendant then phoned her to say he had also left the address but continued to "ring her multiple times".