We approached two traveling couples and invited them to a hot spring facility under the pretext of an interview! The couple, who were meeting for the first time, were asked to take on an extreme mission in a mixed bath with only a towel on! The mission starts with a discussion of daily troubles and gradually becomes more extreme, but despite feeling embarrassed and guilty, they swap partners and engage in cheating sex! Although they know it's wrong, their sexual desires win out over their reason and they instinctively swap and have raw sex and creampie!