Could you please suggest a more natural translation? Or at least point out at the words that are particularly wrong?
'The boy and girl will be dancing' is an option for this translation. Possible scenarios are: 1. To describe a future action at the beginning of a scene in a play. 2. What will happen at the beginning of a celebration when the special guest enters the room.
Although 'A boy and a girl will dance' is technically a correct version of the translation, it sounds awkward and more like the phraseology you would hear from a non-native speaker.
The indefinite articles make it sound creepy. The boy and the girl will dance seems fine. A boy and a girl will dance... the exilir will be consumed and the suns of planet whatever will burn bright red, and only then will the transformation come to pass... Sounds like part of sone ritual when they want a random boy and girl to dance.