Auld Lang Syne by May Lark

Brett had been the bane of Shell’s existence, always making her life harder than it needed to be. Now, more than a decade later, he shows up at a work event smugger and sexier than he has any right being.
A quick coffee catch-up and a little drunk messaging turn into the last fling Shell ever expected to find herself in. But Brett’s life has secrets he doesn’t want Shell unraveling. Will the truth carry them together into the new year, or are old enemies best left forgot?