Green’s Dictionary of Slang

(US) a prostitute, occas. a lesbian.

1942		Davis & Wolsey Call House Madam (1943) 344: The puella – she knows the motions that interest you and is bringing on the mood [...] Lesbian love makes girls go that way.
1971		Winick & Kinsie Lively Commerce 41: On the West Coast a prostitute was often called a ‘puella’.