Has an AFL game ever ended 120-91?
Exactly once. On August 19, 1961, Hawthorn beat St Kilda 120-91, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 120-91 in league history.
That makes 120-91 the 3836th most common final score out of 6,607 that have ever occurred in AFL. One point away, 121-91 has happened 2 times and 120-92 has happened 3 times.