You select the fox option for the idea comes across as kinda silly. How could you become a fox's asshole? Immediately afterwards you began to feel tired and struggled for consciousness. Then the world feel dark. After what seemed like hours you awoke in a deciduous forest surround by ferns and leaves. You were naked, cold and scared, but you weren't alone. You saw a beautiful red vixen standing with her back turned towards you. You felt calm at the sight of her. You wanted to touch her. You wanted to love her. You wanted to... be part of her. Slowly you crept towards her careful not to spook her. There you were right behind her. You could smell the scent of heat. Then she lifted her tail and looked back at you. She was welcoming you to take part in her. You nodded and knelt down behind her. Before you was her glistening red virgin pussy and her shining pink anus. For some unkown reason you reached for her anus. When your finger touched the outer ring you fell unconscious. In your slumber you felt pulsing and heard moans then everything came back. You couldn't feel your arms or legs. Everything was smelling terrible and you heard snikering. The impossible just happened. The vixen tricked you into becoming her anus.