How many letters does the top answer for “composer of the vampire diaries” have?

The most common answer is graham (6 letters).

Crossword clue: composer of the vampire diaries

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

graham 6 letters wd-fact-v3

flour made by grinding the entire wheat berry including the bran; (`whole meal flour' is British usage)

author of the vampire diaries 50% similar → smith

director of the vampire diaries 50% similar → dobrev, wesley, williamson

wrote the vampire diaries 50% similar → smith