How "edgy" is Coupling?

I just saw my first episode of “Coupling” on BBC America.

I looked it up and it was the finale of the 3rd series. I was a bit lost, but it seemed…okay.

Anyway, it was kind of “hardcore”. Are they always so sex-related? Is there nudity? Was this show better earlier in its run? I could see getting into these characters, but am a bit put off if every ep. is one big “sex-fest”, so to speak.

Anyway, any info. you could give would be nice.