A person who composes allegories or interprets things allegorically.
From 'allegorise' plus the agent suffix '-er,' which creates nouns for people who perform an action. British spelling of 'allegorizer.'
In medieval times, the best 'allegorisers' were the church scholars who could take a simple story and find five levels of hidden meaning—it was basically an academic superpower!
Complete word intelligence in one call. Free tier — 50 lookups/day.