Summary: the female most apt to be profoundly affected by the phenomenon of pair bonding is one with prior significant ("in love") relationship(s) REGARDLESS of sexual history.

Morals: if you want a woman who is a virgin or low (n=1) count because of a moral or religious imperative that is your prerogative. However, if you are using n count as a predictor for future female extra-partner copulation (epc) or fidelity, I have some bad news for you: It is not as simple as you may believe.

Pair bonding (pb): a process whereby endogenous (arising from the body) chemicals cause a reaction within the brain's reward circuitry system that causes a (complex) emotional attachment between female and male.

I don't think that pair bonding (PB) is very well understood in TRP. We tend to rely on the simplified (but often inaccurate) representation from evolutionary psychology that links pb to sex but ignores the emotional involvement. That is an animal-based model of pb.

The science on that which pb theory in humans is based is slightly more complicated and there is a key distinction between animals and man: trigger event variable.

In animals this relates to mating activities like hormone signalling, scenting, courtship rituals, etc - physical variables. For humans (because of the neo-cortex and voluntary and complex subcortical function), pb occurs with the release of hormones and neuropeptides (oxytocin, AVP - arginine vasopressin, prolactin) that act on the reward (dopamine) pathways in the brain - emotional variables.

This has been demonstrated many times in behavioral analysis studies with imaging scans and concurrent tissue/blood sampling. Here is one such study: http://www.nature.com/neuro/journal/v7/n10/full/nn1327.html

It is theorized that this response is more pronounced in females as they are more emotionally labile. Additionally, it is thought to provoke less of a response in men due to testosterone inhibition of the key neuropeptides. This makes sense to me as women are more prone to regard 'feelings' as most important. It would not surprise me if their neo-cortex was more responsive to emotional (love) cuing. The result is that pb is primarily a female:male phenomenon that is weaker in the reverse.

This is an area where animals are not as complex as humans in terms of brain functioning. Pb is a biological occurrence within the expertise of neurology. It cannot be adequately understood as a psychological occurrence which explains why evo psych types often misunderstand or misinterpret the research.

The implications for this are that a virgin may have extensively pb'd with a sweetheart with whom no sex (differing definitions) occurred. Alternatively, a woman who, fully subscribed to the belief that sex can be a recreational activity not requiring commitment, could participate in the hook up culture and not experience significant pb.

Pitchfork Theory of PB: I hypothesize that the most dangerous woman to associate with in a LTR is the n=1 female who engaged in a "high school sweetheart" relationship. By this I mean that couple who start dating in their early teens and were exclusive throughout the years.

A perfect characterization is Romeo and Juliet, a fierce young love that separate due to circumstances (parental interference, family moves, or differing colleges after graduation). If pb in adolescence is comparable to addiction (which it should be as both operate on the neurolimbic reward pathway) then the behavior reinforcement should be stronger and more likely to persist. She may never be able to effectively pb to that same degree again...forever.

Tl;dr: You cannot examine only n-count to make an accurate prediction of female pb occurence(s). You need to know how many crushes she has had too. Love (emotion) is more significant than sex (physical) for creation of human pair bonding, especially in females. Beware the 'Juliet' (n=1) female.

Edit:

(1) A common mistake of confusing correlation with causation < Thats very nice but virgin bride still statistically offers her more happiness as well as offering you the most stable marriage possible (80% marriage success rate) with the lowest divorce rate.

This is an instance of mistaking correlation (an association between two variables) with causation (one variable directly brings about an effect on the other). The reason that there is a correlation between low n-count and low divorce rate is religiosity and moral imperatives. A woman who is an adherent to a religion which forbids pre-marital sex and limits/strongly discourages divorce, will fulfill both of the criteria being captured here. The (uncontrolled) presence of that sub-population within the study group will skew all data.

I suspect you could demonstrate a correlation between low n-count and conservative political beliefs but the idea that there is a causal element in this latter example is specious. Sometimes the most obvious explanation for data is overlooked (or ignored if the proponent has a narrative they wish to fulfill).

(2) An example where male and female differ on emotional component:
Another situation may explain the differing attachment affinity (part of pair bonding feature) between males and females. Consider the definition and reaction to emotional versus physical cheating between men and women. Males tend to shrug off a revelation that their SO has been texting and sharing with a male "friend." However, we lose it if we find out she has engaged in sexual activity with this same "friend". Women, on the other hand, tend to take what they consider to be emotional infidelity just as seriously as physical. I suspect that this once again is because they pb in a different way than us and emotional involvement is more involved.