pronoun
Archaic feminine first-person pronoun, mainly used by prostitutes in the Edo period. Not used in modern Japanese outside of historical or creative contexts.
「わちきは、そうは思いませんよ」と遊女が言った。
"I don't think so," said the courtesan.
Standard polite first-person pronoun used by both genders in modern Japanese. わちき is an archaic feminine variant with a very different social context.
Casual feminine first-person pronoun in modern Japanese. わちき is much older and more specific to Edo-period courtesans.
The exact derivation is uncertain; it may be a sound change from わたくし or わたし used in Edo-period red-light districts.