Hellflower by George O. Smith

It looked as innocent as a gardenia...but the Hellflower’s perfume turned any woman into any man’s woman. The haunting, pungent scent aroused desires too fierce to be slaked by ordinary passions—and left its victims burnt-out husks! Charles Farradyne knew that no woman could resist the Hellflower. Yet Carolyn, the girl he wanted above all to possess, smiled when he gave her the deadly bloom—smiled and inhaled the perfumed poison.
Hellflower is the fantastic story of a lovely woman who was not quite human—and of a man who went through heaven and hell to win her.