Hailey Baldwin asks Bieber to stay monogamous?

Model Hailey Baldwin has reportedly told pop star Justin Bieber that had to be monogamous if he wanted to date her.
The 19-year-old model was first romantically linked to the 21-year-old singer last year, with the pair fuelling the rumours during a New Year's holiday.
Following their vacation, it was said that Bieber, 21, had been getting close to Kourtney Kardashian, something Baldwin was not impressed about, reported Us magazine.
A source said, "She demanded he stop stringing her along. She said he would lose her if he didn't man up and show he was serious about her."
Apparently it was 19-year-old Baldwin's forceful attitude that proved so impressive to Bieber, and he decided to give the relationship a chance.

The source added, "Justin has never had a woman act like that before. He couldn't say no. So he's been seeing her again and is with her all the time."
The pair have been friends for several years.