Or rather, to give themselves a little bit of privacy.
Dragons were extremely passionate creatures. The thought of having a wild fight turned them on in no small measure. So when Elliot said he needed an hour to recharge his energy, the two dragons had immediately agreed.
And by some unknown signal, they had immediately decided that they would spend the time waiting for Elliot in the most carnal and pleasurable way they knew - mating.
Ever since they reached planet earth and gained the power to morph into human beings, they had been fascinated by how different but still highly pleasurable the mating mechanism was, and they had spent quite a bit of time doing exactly that.
After they had cleared the area of potential enemies and set up a private barrier around themselves,, of course.
And at that moment, they flew towards the distant hill at top speed. They couldn't wait to get their hands on each other!