Well this is awkward!
Bad boy best man Spencer Matthews was caught stealing a cheeky kiss from Donna Air - the girlfriend of his soon-to-be in-law James Middleton!
Although Spencer's act was no doubt harmless, James certainly didn't look happy!
Spencer is famed for his lothario reputation and famously dated a string of women when starring on UK reality series Made In Chelsea.
Spencer was one of the first guests to arrive at the wedding of his brother, James and Pippa Middleton.
More details to come.