The Left Corner Bracket symbol (「). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Punctuation.
The quickest way is to copy 「 from this page and paste it anywhere. You can also insert it with its Unicode, HTML, or alt code listed above.
「 is U+300C (decimal 12300).
Use 「 in HTML to render 「 on a web page.
On Windows you can type it with Alt+12300 (hold Alt and enter the number on the numeric keypad).
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