Blame It On The Blackout by Heidi Betts

In the pitch blackness, trapped between floors,Peter Reynolds had almost convinced himself that the woman in the suddenly too cramped-for-comfort elevator car was not off-limits...and that the desperate passion they shared would not change everything.

But then the lights came on, and Peter knew that he’d crossed more than one line. For Lucy Grainger was his secretary...and now, quite possibly, pregnant. If Peter were any other man, Lucy would make the perfect wife and mother to his children. But he was not the marrying kind for reasons Lucy could never understand. Yet, if that were true, why was he secretly hoping that the stick turned blue?