[This guy has still forgotten a lot of things - about Fay, about the kids, about Tomoyo... Not his parents, though. In fact, he remembers them perfectly - and how they're still happily alive and waiting for him in Suwa once he leaves this place. ... Right?]
[So something is DEFINITELY off with him, should you run into him. He's searching for answers!!1 aka Fay didn't tell him shit about having forgotten stuff, nor does he know to search for his memories, obviously, so he's mostly wandering around trying to figure out why things are not making any sense for him (things aren't adding up, etc).]