Thought of a cute AU idea where Gaon has a cooking youtube channel pre-canon where he doesnt show his face but cooks whatever his subscribers ask for/makes on-request step by step tutorials for beginner homecooks and college students. Yohan subscribes to that channel while looking for recipes to make for Elijah after the church fire, trying to replicate dishes from her mother that she liked, hoping to get her to eat again. He anonymously comments and asks Gaon for tutorials on some of those recipes, and while little Elijah doesnt eat everything, the familiar taste comforts her, which Yohan appreciates enormously. He thanks Gaon, reports that the recipes are a success with his niece, and regularly suggests other foods Elijah loved. Gaon obliges and gladly films some more tutorials, keeping this person's niece in mind and wishing her good health.
Then, around the time Gaon gets into law school he becomes really busy and stops updating the channel regularly. Yohan sends kind messages but doesn't get a response bc Gaon has long since logged off and has even forgotten his password. Fast forward to canon, Yohan sees Gaon get really busy in his kitchen, and decides to watch him make one of Elijah's favourites (and maybe gives him one or two details about her preference). Then he notices how the proportions, the way Gaon goes about the different steps and secret ingredients are the same as that youtube channel he used to watch years ago. Yohan off-handedly asks him if he's seen the tutorials from that channel too. It's then that Gaon realises that those heartwarming comment from an uncle cooking for his little niece were from the very family he's inserted himself in