I believe he was the basis for the character "Jack," and Jonathan's then-girlfriend (who would later go on to inspire the "Maureen" character in RENT) was the basis of the character "Milky White," owing to her gorgeous complexion. This led Larson and Sondheim to stumble on the inspired casting of Bernadette Peters, herself with a milky white complexion, to replace Daphne-Rubin Vega, the original choice for The Witch.
Wild how it all overlaps, no?
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