Technically they did sleep together, even though they didn't do anything. Prince Xanfon was too tired, so he spent the night just sleeping and hugged Princess Althea very tightly. Sometimes he woke up at night, just to make sure that his future wife gets a blanket and wasn't bothered by his presence.
Princess Althea had woken up at night, caught Prince Xanfon who was staring at her. "Why are you looking at me?" she asked, rubbing her eyes slowly. "Do I snore in my sleep? But I don't think so."
"You don't snore, but you disturb my sleep."
"Should I just go?"
Prince Xanfon shook his head. "You have to be here." He hugged her. "Even though I'm in torment."
"But why? What did I do?"
"You awakened my Mirah's energy."
GULP! Princess Althea glanced at Prince Xanfon warily. "You're not going to do that to me are you?"