Yeah, this is another silly one that relies on random luck. It assigns you your rival but lots of things can then happen to that rival in the time it takes you to get to the end of that aspiration and there doesn't appear to be a script to give you another one. Maybe if you quit and sign up for another after school activity it might but who knows.
It should have just been the very first aspiration on the list. You could declare your rival right at the beginning and then the rest of the aspiration could have been centered around an actual rivalry.
