People draw so much incest of these two just because of one support conversation and sometimes I’m just like reeeeeee
What can I say? Doujin artists like incest... although, really, it's not like there isn't a TON of material for that in Fire Emblem. Priscilla's "No, seriously, I definitely want to marry you, big brother, you promised me and I'm holding you to it" comes to mind, as well as Lachesis, and basically everything about Fate's royal families is just a massive "technically not blood related" incest orgy.