From the moment he stole her precious rubber ducky, Kelsey knew she would always loathe Atlas.

Atlas Warren and Kelsey Griffin have only ever agreed on one undeniable truth: they disagree on everything else. Kelsey has never seen Atlas as anything other than her brother Jesse's irksome best friend, and he has always seen her as nothing but a naïve nuisance. Years of constant bickering and simmering hatred throughout their childhood shaped a rigid line between them - that was until Atlas skipped town abruptly and without a word. That day, Kelsey's life became a lot more simple.

...Until now.

It's almost been two years since Atlas' disappearance when he shows up to the Griffins' home unannounced and in need of help. Before Kelsey knows it, she's forced to share her space with her brother's insufferable ex best friend on a permanent basis. To make things worse, he seems hellbent on keeping his extended disappearance a secret from her.

They should hate each other even more now than ever. Atlas is secretive, Kelsey won't stop pestering him until she knows why, and most importantly, they still can't stand one other. So why, against all odds, is that once impenetrable line beginning to blur?