The prince is not the beast.
The youngest prince chose. He chose the castle and the strange amusements inside and most of all he chose the beast. It was no fault of the prince's father, where he ends up, unless you go back years and years and then it is entirely, terribly his fault, for if we are to follow the archetypes to the letter the father is entirely responsible for the prince's beauty. Whether this is a curse or a gift depends entirely on your point of view.
The beast, who is actually a man, does not wish company from the prince, does not wish to keep him, but in the same breath he has no intention of letting him go- a week may become decades and the prince lies, the prince always lies. The beast, who is actually a scientist, wants to take the prince apart and figure out how he works, but the prince says
"I am already in pieces. The real challenge is in putting me back together again."
"I have not yet failed at putting things together, better than they were before." There is a metal mask which proves this statement false or true, depending on your point of view.
The prince pours all his fragments, shattered sharp and sparkling under a microscope and you can pretend this is only a pretty metaphor if it helps you sleep at night, but the beast is actually a scientist and we already know that the prince lies.
The prince is restored beneath the beast's hands, easy and malleable; the beast already knows how to make masks, this task is familiar. One wonders how far down the masks go, really. Shattered mirrors still show you your reflection, and the beast has no love for mirrors.
The prince goes home eventually, of course. Not even the beast, who is actually a king, can stop the story. And just as is proper, the prince returns, quick-footed and fierce.
"You are dying," says the prince, and then there is an apple. It can be a rose, if the cognitive dissonance is too much, but it is golden and tart on the tongue of the beast, who is prideful above most things, so it is a good thing that the prince, who is actually a god, always lies.
"I know you wished immortality through something you created by your own hand," the prince says, meaning 'I'm sorry'. The beast, who is now actually a god, takes it as confirmation. There are fireworks when they kiss. They don't stop.
The prince is not the beast