The paper crane vaguely had characters on it, and upon opening it was revealed to be an invitation card.
A formal invitation card is needed before a proper visit to let the host know the background of the visitor. The vigorous and forceful cursive on it read—
Greetings from all fellow cultivators of the Liao Family Fist.
I am Zhou He of Wudang, who has undergone the Blood-Exchange and Spirit Refinement of Divine Fetal Breathing.
A month ago, at Richard Restaurant, I chanced upon three individuals exterminating demons and saving people, an act which I greatly admire.
I specially visit today and I hope you will not hesitate to grant me an audience.
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A few lines of casual conversation, but it is the standard invitation among martial artists, clearly stating the background, realm, and purpose of the visitor.