Totally. On the MLW forum there's a post where he is whining about being jealous of other twilight humpers, and he says that he knows she isn't actually real and that she is a public figure so it's okay for others to fantasize porking the poor thing.
Two posts later he starts going on about how she's his real twilight and they have an IRL relationship, and everyone else is just fantasizing about someone else or something convoluted and crazy. So he almost admits that he doesn't fully believe she's real...and then goes back on it. And this is after she supposedly woke up next to the hairy, crying neanderthal.
Okay so proof she's not real: twilight is pretty, popular, and talented. Jin is a fucking creepy ass dude. If she were real she would have run the fuck away as fast as possible and found some other dude to bone who wasn't a brony.