In the scene described, Fang is unexpectedly giggling hysterically, which is unusual for his character. The excitement is centered around a jackpot, highlighting a moment of surprise or amusement for Fang.
The narrative humorously notes that Fang doesn't normally giggle, especially not in an exaggerated way, emphasizing how out of the ordinary his behavior is in this moment. This creates a playful and engaging atmosphere in the story.