On a side note, what idiot would have unprotected sex if he or she were going to cheat (in other words, there shouldn't be any semen residue in the underwear anyway)? So just because the test result would be negative wouldn't necessarily mean that the person hadn't cheated. Plus, I know I don't particularly like wearing soggy panties; I usually clean myself up really well before I'd be putting panties back on anyway.

__________________
Communication is the key.