The air around them is warming. Magnus, largely impervious to temperature, doesn't totally realize that he's summoning summer in his happiness; he's more focused on Galahad saying friend. He wants to let both of them sit with this, for the moment, but if truth be told, he also has a bit of an agenda: He'd taught Claudius how to say 'I love you,' and he wants Galahad to be able to understand it for what it is if Claudius ever says it to him.

He signs friend back.