In every fighting class, the top students rise to the top, but there can only be one who is considered the best. That's determined simply by having them fight... and the one who quits or is knocked out, will stay in her place as just another girl in the dojo, and everyone will know who the top girl is. Kicks, holds, it's all here to determine the top student.
With 1 fall for each competitor, the final fall will decide the outcome - both girls spar and attempt to land blows, so they can be the top student.