They're jumping in the sack with someone. Apparently, some guys find these types of women compelling - or at least attractive enough to sleep with.
Guys who sleep with any woman who will lay down for them need to take some small responsibility for the sluttiness of these women. Sexual immorality is sexual immorality, no matter the gender of the perpetrator.
"Sexual immorality is sexual immorality, no matter the gender of the perpetrator"
Here here. Or hear hear.
Men who screw around are sluts. Amazing how all the words only apply to women, though.