Notice how on the computer screens not all the team members have the same amount of hearts? That’s some super-subtle foreshadowing!
Thalia would be the MVP on the school Fireball team, but she can’t stand abbreviations. She also has no patience for “text speak” and doesn’t understand why people would ever want to shorten words or phrases. Thalia argues that people who try to save on letters & words lose something more valuable in the long run! Luckily, she lives in a future that celebrates verbosity and run-on sentences. And presumably, twitter is long extinct, or allows some form of expansion on their character limit.
It was surprisingly tricky for me to think of other things the bears might think BFF could stand for in this context. Boastfully Fun Father? Boy From France? Brother Flunking Frequently?