Japanese “reserved” button emoji 🈯 is part of the Symbols and Alphanumeric Symbols emojis. On some systems it can be accessed by using :japanese_reserved_button:, :ja_reserved: or :u6307: shortcodes.
It was approved as part of Unicode in 2010 so it should be displayed properly on all devices.
Tags: Ideograph, Japanese, Japanese “reserved” button, “reserved” and 指