Lots of innuendo. A running joke in the first episode involves a Polaroid of a penis. The picture isn't shown, but talked about a lot.
Barb tells Jack that he better not try and "slip a cock" inside her because she is in a committed relationship with someone online.
One of the main characters is a stripper, seen at the club and in revealing outfits throughout. Multiple instances of revealing tops on women showing cleavage. Strippers seen in different scenes throughout the series. Main character shown without pants on multiple times.
Sides of beds are shown jolting around to indicate sex.
A man touches his girlfriend's buttocks on a couple of occasions.