Tomb-raiding my wealth _ Tomb-raiding fortune-telling novels

Why is it so famous to say "kill me, it's my treat"? What does this mean?

I saw Xiaohua on the other side wearing a suit and his signature pink shirt. While texting, she came up to me and arranged her hair without looking up. Then she looked at the opposite person and said, "Send the scattered leaves to the' old place'. If you meet Wang Baqiu, it's my treat."

Grandpa Hua is very domineering.

There should be master Hua and naive friendship.