>Why does Gryphon let Reimu pick this fight with him?
>

Everyone's patience has its limits is how I read it. The man had things to be doing that Reimu was interrupting, which by itself wouldn't be enough, but her rather dire remarks about Remilia likely tipped the scales from 'benefit of the doubt' to 'the hard way it is'. Her smugness of 'when I defeat you' is also an attitude that screams for a large helping of humble pie. Maybe a full on Jedi master would have still tried to keep the peace until the absolute last possible moment, but G would be the first to tell folks he's no Jedi.

	-={(Astynax)}=- "Sometimes percussive maintenance is required, even in people."