Guy wasn't sure how smart it had been on Celes' part, but she had gone ahead and healed Dias up anyway. Guy knew it would be to their advantage so he couldn't complain too much, but he still felt guilty when he saw that the woman was on the verge of collapsing.

It didn't help that there wasn't much he could do about it. She was in danger, yes, but he didn't know if it was bad enough danger that his phobia would temporarily disappear for the sake of helping her.

Besides, Claude and Dias were right there to take care of her if she needed it, and so Guy continued to watch in concern. They needed to get her to a place where she could lay down (Hughes' room, had she said?).