Then Marvolo insisted that Sirius at least take part, as Harry’s guardian, as was appropriate for this sort of arrangement. There were protocols to all of this, after all. Arranged marriages with actual contracts didn’t happen often in Harry’s generation; mostly purebloods from families who cared about remaining pure simply knew everyone who was a reasonable candidate and found a match somewhere in there. They had, however, still been somewhat common in Marvolo’s generation and not unusual in the Marauder’s time so Sirius had been taught the protocols.