>>105954828I always imagined he had a crush on real Frankie, but a sort of idealized version of her that doesn't match up with reality at all. So his idealized version becomes his Friend, only to find out that even his ideal version of her isn't exactly perfect and probably screws things up for him more than anything due to being comically ditzy. So though her he has to realize the differences between fantasy and reality, learn to take care of someone more childish than he is and take the role of a big brother, and to respect Frankie herself as an actual person, rather than an idea.
All of this is total headcannon bullshit, mind you, but I can definitely see the potential here.