You are

The Deep Diver

“Three weeks in and you're correcting other foreigners. Nobody asked you to.”

Hanfu, calligraphy, the toast order at dinner, why the red envelope amount matters — you went for the layer under the sights. It makes you very good company and slightly exhausting at a group dinner.

Saves a card you can post. It has a QR code, so whoever sees it can take the test too.