Sting And Shatter. Undertow Sins, #28

The thing that can save you is also the thing that can kill you. Waverly Croft is a pragmatic financial compliance analyst whose life is falling apart. To clear her late father's crippling debts, she travels to Thorn Island, a remote fifty-acre property off the coast of Maine, intending to sell it to developers and walk away. But the island is far from abandoned. It is occupied by Ajax Thorn, a grieving, fiercely territorial marine mechanic who tends to forty beehives left behind by his deceased sister.
There's just one problem: Waverly has a severe, life-threatening allergy to bee venom. One sting could kill her. When a dense, days-long maritime fog rolls in, Ajax secretly disables Waverly's only boat back to the mainland, trapping her with him. What follows is a tense, claustrophobic game of survival and unexpected attraction. Ajax meticulously controls Waverly's environment, drawing safe corridors and keeping her away from the lethal hives, effectively making her his prisoner to protect his sister's legacy.
As the isolation deepens, Waverly must navigate a complex dynamic with a man who is simultaneously her captor and her absolute protector. Trapped in a farmhouse that smells of beeswax and woodsmoke, Waverly uncovers hidden ecological research that might save the island-and realizes the greatest danger isn't the bees outside, but the burning, undeniable pull she feels toward the man keeping her caged.