My Wife, the Snake Demon

Gavin Grant marries Jade Wynn. Colleague Sean Shaw lies Jade is a snake demon, weak to roosters. Gavin, misled by clues like snakeskin and Jade's fear of roosters, suspects her. Jade is a hidden heiress, not a demon; clues stem from her special constitution. Gavin realizes Sean was the villain, sabotaging their relationship. Gavin wins back Jade, misunderstanding resolved, villain punished.