There were no actual protocols for dealing with the offended scion of a Demon Lord, but the general recommendations, as found in most grimoires that didn't finish in bloodstained tatters, were extreme courtesy and a good reason not to slaughter or torture the summoner on the spot.
"Would you be interested in the whereabouts of Dante, perhaps?"
After all, it had been Dante he'd been trying for. He hadn't known that Sparda had two offspring.
Such a shame; they'd have made a lovely matched pair in his bed.
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