Oh man, I remember this from my childhood! Absolutely brilliant. Also starred Cleo Roccos (the bird off the Kenny Everett show). The one bit I remember clearly is when she and her boyfriend are talking and he says "Do you love me?"
"Yes" She says
"Even down to the mole on my arm?" he asks
"Yes, even down to the mole on your arm" she replies.
Then as she looks down to the big mole on his arm a real (fake) mole bursts out of it and bites her throat out!!!
Top stuff, would love to see it again.