Ty composed himself, took a deep breath, and said, "...No! I can't defile someone who doesn't want it." He withdrew his hands from Mary, and said, "Mary, I'm sorry. Are you OK?"
Mary's fearful expression turned to an evil smile, and she laughed in the voice of the succubus before the room around them turned to darkness and she faded from existence, the succubus's laugh continuing as it spoke to Ty in his head again.
"You think you're so pure of heart, don't you?" the voice teased. "You don't seem to realize, this room isn't a trial of purity, it's a trial of masculinity. With a result so submissive, it's obvious what will fit you."
An intense and weird sensation spread through Ty and he felt his body slowly start to reshape itself according to the succubus's whim. "Your body is only the way it is by accident of birth," the succubus said, "so now I'm going to fix that accident, and make you how you should be."
Ty winced as he saw his figure contort- his muscles became more petite, his skin softer and smoother, his figure shifting outwards until he had curvy hips. "This form fits you better, and you know that," purred the succubus. "You were no good as a boy, but you'll be so good as a girl."
The instinctual desire Ty felt to question her was muffled by the surge in sensitiveness in his chest. His eyes widened as he saw his nipples expand and turn erect, soft flesh forming as mammaries developed. "Mmm, isn't that nice? The pleasure of the female body is so striking when you've only known life as a male," the succubus said. "I bet there's loads of fantasies about having your boobs played with running through your head right now." She was right- Ty couldn't help but imagine someone cupping his big soft chest and sucking on her sensitive nipples.
Ty's hands moved to her boobs and she moaned so loud at the sensations she surprised herself. She felt a surge of sensation in his cock and his eyes flew open as he saw himself ejaculate hard into nothingness. He hadn't even noticed how he'd been calling himself she just before.
"Now you're gonna relinquish the last male part of yourself and turn fully female," Ty heard the succubus's voice instruct him. "I hope you're ready for your castration and emasculation, cause ready or not, here it comes!"
Ty gasped as he felt his testicles get tugged up inside him, the succubus's magic transforming them into ovaries and linking them up with a feminine reproductive system. His scrotum hunched up and sank into her, while his penis turned flaccid and shrank and shrank. Before long, vaginal lips and an opening had formed between Ty's legs and her cock had fully turned into a clitoris.
Ty took a little while to recover from her transformation, and the succubus told her smugly, "Now it's time to finish you up..."