A person who has dated,married,or had sex with someone you know is considered tainted.
Their level of taintedness makes it questionable as to whether or not you should be involving yourself with that person,usually, and especially in an intimate manner.
There are several factors involved with determining the degree of a persons taintedness, such as;
-How well one knows the person or people, that the tainted individual was with (and if you know and dont like that person, then the taint factor is waived and becomes more of a Yeah, I banged that assholes ex!)
-How long ago that relationship or encounter took place,
if that person had been with the tainter last night, their taintedness would be just about radioactive...
on the other end, there is a standard five year statute of limitations and the taint in most cases has worn off.
-Some degrees of taint are infinate, such as Brothers ex-wife, exs of parents etc.
-The combinations of situations and connections are so numerous that there is no exact science for taint determination and each case must be evaluated on its own.
In most cases there should be an individual who has the experience and knowledge to act as Judge of the Taint to rule on tainted individuals for you or your social circle,and that persons judgement should be taken into consideration before going ahead and doing whatever you were going to do in the first place.
