"I wasn't sure if you wanted to keep the wounds until we had returned to the shoreline."

While the burns will take some effort, Skellig is full of Light at the moment (even as upset as he was just moments ago) and has plenty of energy to spare; he carefully allows his hand to settle on some of the bare skin where she has yanked her feathers out, but doesn't touch the burns outright.

The way their bodies are positioned, it does not matter if any of the crew are sneaking and stealing glances their direction; they will not be able to see that it is him doing the healing (not that there are any outward signs of it anyway) to her skin. He takes the pain away first, then sets on getting rid of the tissue damage.