Evan didn't presume to try to bar Niks from the alien that appeared in front of him. He didn't really think that it was a threat, for one. For two, he knew he'd get hit if he blocked her view of it.
But he did place himself in front of Sabev. It was more for her sake than anything else. It was clear that this alien could harm any one of them if it wanted to, and the fact that they were all still alive and it was speaking words of explanations, made Evan feel like they were all safe for the time being. But this would be yet another new thing for the little phoenix, and he wanted to let her know that he was there to hold on to, if she needed him.
He looked at Niks, curious to see what her face would be like. Would he read there the astonishment and wonder that he was feeling himself?