Transformation: The White Snake's Love

A top student at the police academy, he suffers a tragic mishap on his very first case. When he wakes up, he discovers he has become a white creature that has been starving for a long time. Driven by hunger, he bites an immortal, and from then on becomes the immortal's pet. After eating one of the immortal's fruits, he finally turns human. Huh? Wait, something's wrong with my gender! How did I turn into a girl?