It's fun, but spoilt because they couldn't make up their minds whether they were making a realistic movie or a fantasy. Most of it is excellently true to life, so the occasional pure fantasy moments - like taking a nude pony out on the public road - are jarring. And the sequence about the Domme's "darkest fantasy" is too thin a joke to be made a major plot point.
And, of course, there's the basic problem of why on earth the Domme falls for this graceless vanilla nerd when she's got more boys and girls than she can use!