Goh always dreamed of being able to find Mew and add them to his team, but who would've thought what it would take for them to meet is Mew transforming and regressing him, as well as Ash and his Kalos friend Serena.
I think he's either awestruck that he's finally able to be on the same level as the Legendary, or that Mew is just as much of a cuddly, cheerful potty-pants baby as they both fill their diapers. At least they'll make for chipper changing time buddies.
