Right White Corner Bracket

It ends a quote or title opened with 『. Japanese frames an outer quote with 「」 and puts a quote inside it in 『』.

Chinese rules differ: Taiwan also uses 「」 outside and 『』 inside, and Mainland Chinese vertical writing uses corner marks too, so there 』 does not signal a title.

Japanese quotation marks are documented in fiction dialogue by the 1880s, separating speech from narration. That dates the convention, not this exact double form.