Has an AFL game ever ended 120-115?
Exactly once. On June 4, 1928, Richmond beat Fitzroy 120-115, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 120-115 in league history.
That makes 120-115 the 3884th most common final score out of 6,649 that have ever occurred in AFL. One point away, 121-115 has happened 1 times and 120-116 has happened 1 times.