The ongoing story in my head is that Nins and Olivia would bring Inigo over to Cherche's place often to play with Gerbear, and Inigo didn't know how to make a dragon stone to contain all that lizard goodness, so Gero just thought his mom had cool friends who had great taste in lizards.
Years later, they're on different continents, House Virion is invited to a party in Ragna Ferox. It's Inigo's 16th birthday, an important milestone or something. Gerome thinks it's cool that those nice lesbians are having a party for their shiny Wyvern baby. He must be old enough to be a war mount now or something.
So they show up, and uhhhh, turns out Inigo isn't a shiny Wyvern at all. So Inigo remembers Gerome as the extremely nice boy who would never leave his side, and Gero remembers a sick ass lizard.
Gerome is terrified when he realizes that he has to interact with a person instead of a sick fucking lizard.