Ok. Ramza met Yuffie on a Shoopuf airship ride. She was getting airsick and he kind of freaked out until he found a vendor that sold potions to help her stop dying. From there, they hung out and bonded over time until he basically adopted her as a surrogate little sister. And he punched Luffy in the face when he thought Luffy kicked her off his crew. And gave MarKus the shovel talk when he heard they were sort-of dating.