I totally missed that earlier.
From my awful knowledge of anime-Japanese:
Takajou goes zooming past and crashes. Takamatsu stops to ask if he’s okay before noticing who he is talking to. Takajou apologizes for the crash, and then stops once he realizes who he is talking to.
“I am you??” They both say.
Takajou quickly shuts the idea down, introduces himself, then runs away, not before they both namedrop what franchise they come from.
So it’s the running joke.