My Secret Alpha is My Lucky Puppy

She paints and the work goes out under her younger sister's name. Their father arranged it that way, favouring the younger girl, who was born outside the marriage, and he keeps his elder daughter on as a cleaner in the gallery where the canvases hang. He then sells her at an underground auction, put up as one of the lots. A man there claims her and has her sign a marriage contract straight away, and she signs without knowing who he is. He turns out to be useful against her father, and the revenge she takes is hard. He is the alpha werewolf the city stays out of the way of. Ten years ago she took in a stray puppy off the street, and that was him. For years he has been spending millions on every painting of hers that came up for sale.