Her Other Man by Linda Verji

Amara Sethy has always tried to look on the bright side of things. Sure, her boyfriend, Justin Taylor, has asked for an open relationship, but at least he didn’t go behind her back and cheat, right? Maybe bringing other people into their relationship isn’t as bad as it sounds. Maybe they do need to explore some more before getting married.
When Justin actually starts dating other people, Amara realizes that there’s no reason for her not to play the game too. So, she sets out to find a partner of her own. Enter Marcus Reyes. Marcus is a sworn bachelor who is only looking for a little fun, which makes him perfect for Amara.
But perfect can turn into complicated really fast. And a little fun can become real feelings in the blink of an eye.
Now Amara has to choose. Will it be Justin, the relationship they’ve nurtured for ten long years, and the stable future he offers? Or will it be Marcus, the friend with benefits who makes her see all the things she’s been missing?