The Japanese postal mark, 〒, is referred to as the yuubin kigou (postal symbol) or yuubin mark (postal mark) in Japanese.
There are a few variants of it in use, such as one version wrapped in a circle, or wrapped in a circle with a sine wave above it. Most interestingly, though, is the postal mark face!
This face is identical to Number-kun's, but according to the Japanese postal service, Number-kun is only Number-kun when he has a body. To me, it is still Number-kun in spirit.
Because this character was used in communications, and even in the address book, it has been included in Unicode too. What does that mean? It means you can type Number-kun on your keyboard!
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