Song: "Smell Yo Dick" (2007)
Though comedic in concept, women have been smelling their man's dick for years to find evidence of infidelity (See: Mötley Crüe fucking burritos to mask the scent of groupie poon from their girlfriends). It's not a terrible way to go about unearthing the truth but it certainly doesn't end well either way.
1) He's cheating, and you now have the musk of another woman's vaginal juices trapped in your olfactory.
2) He's not cheating, and you now have that sweaty-scrote, boiled peanut scent trapped in your olfactory.
Ladies: Stop Smelling Dicks. Track the GPS on his phone instead.