Couples' Sex Showdown 2: The loser's girlfriend gets fucked inside! SDMU-874

A group of ordinary couples were invited to a lubricant battle! Whoever could ejaculate inside the other's girlfriend first would win! But before being penetrated, the woman would be considered "welcoming" if she could perform anal sex, oral sex, breast sex, or buttock sex until ejaculation occurred! What would the couples, who wanted a large prize, do?