Hello! You asked the question, please use the homophonic sounds of Kang Kai and Pei to form a wedding theme. I think: Kang is a surname. Logically speaking, one cannot use the homophonic sounds to make a fuss, so we have to make a fuss about the homophonic sounds of the two words Kai and Pei.
Analysis of the first character: Kai, Kai, Kai, Kai, Gai, Xing, etc. have 35 homophones. Because they were named for weddings, they can harmonize with Kang. For a better match, you can choose the meaning of Kai==joy.
Analyze the second word: The homophones of "pei" include "pui", "pei", "偵", "怌", etc. There are 33 homophones in each word. I think the more suitable word for a wedding is the word "pair" == Jia There are other phrases that are not as good as this literal word, but this one is more appropriate.
I personally think that the best name (for this wedding) is Kang Kai Jiapei, please refer to it! Thanks!