You find out what the scent is. In front of you is a beautiful female dog. The scent overpowers you, as new instincts kick in.
You sniff her all over. You go behind her. Your penis changes from human to dog. It may retract into a sheath...
But not yet. A female needed pleasing. You climb onto her back, and thrust into her. You feel so much pleasure, and as you do so, your tail elongates, and you feel some fuzz sprout all over your body.
You climax, and ejaculate into the female. You feel very refreshed and satisfied.