On the first episode, when they are flying around and different places quickly flash by, on one of them, they go past a building with a radio station billboard out the front(either advertisement or the actual place, I don't know) and when you pause it, it looks like this :-

___________________

| 105.5 |

| |

| WTFU |

|___________________|

The W, T, and the F are all connected, and the U is separate. Now for you that don't know, the W, T, and the F is a swearing thing people say when they are confused, maybe the creator thought that it was confusing that we saw it?