Aside from the other things that got mentioned in the reply after this, the main thing is that it was his estate being auctioned off (because of his death) that started the whole manga, because that auction is where Zagan bought Nephy (who was already apparently bought by Marchosias, but hadn't been delivered yet before he died). And so like this chapter hints, he's probably a lot more related to Nephy than we previously knew+more relevant to the manga.