PAPER: A sixth personality domain that is independent of the Big Five domains:

The psychometric properties of the HEXACO Personality Inventory in a Japanese sample
http://onlinelibrary.wiley.com/doi/10.1111/jpr.12045/abstract

Abstract

We investigated the reliability of the HEXACO-Personality Inventory (HEXACO-PI) using the NEO Five-Factor Inventory (NEO-FFI) and the International Personality Item Pool (IPIP) Big Five scales in a Japanese sample of 492 respondents (mean age = 20.4 years). The psychometric properties of the HEXACO-PI were examined and found to be satisfactory. The results of the factor analysis showed that the six hypothesized personality domains were found independently. A total of 307 participants responded to the NEO-FFI and the IPIP Big Five scales. The results showed that the five domains of the HEXACO model corresponded to the Five-Factor domains and were relative to the Big Five personality domains as a whole, but the sixth domain, Honesty-Humility, showed weak to moderate correlations with some factors of the NEO-FFI and the IPIP Big Five scales. These results suggest that the Honesty-Humility domain is independent of the five fundamental personality factors and that the HEXACO-PI is a useful and reliable questionnaire for investigating personality structure in cross-cultural and other context.


It appeared that the issue of the fundamental personality dimensions was decided by the Five-Factor (or the Big Five) model, but since 2000 a number of lexical investigations in various languages have shown that six factors repeatedly emerge (Ashton et al., 2004) as dimensions of personality. The six-factor “HEXACO” model consists of five dimensions that are similar to those in the Five-Factor Model, with an additional “Honesty-Humility” dimension. This sixth factor measures individual differences in peoples' sincerity, fairness, greed avoidance, and modesty that are not accounted for by the Big Five/Five Factor questionnaires. ............ The name HEXACO derives from the initials of the six domains, Honesty-Humility (H), Emotionality (E), eXtraversion (X), Agreeableness (A), Conscientiousness (C), and Openness to Experience (O).

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Lee and Ashton (2008) reported that a similar six-factor structure was found in twelve independent lexical studies of personality structure based on the results of rating an extensive number of adjectives that describe personality traits in the following languages: Croatian, Dutch, English, Filipino, French, German, Greek, Hungarian, Italian (in Rome and Trieste), Korean, Polish, and Turkish.
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As Ashton and Lee (2007) demonstrated, the HEXACO factors of Emotionality and Agreeableness are not identical to the similarly named factors in the Big Five model. Specifically, HEXACO Agreeableness hypothetically shows positive correlations with Emotional Stability and Agreeableness of the Big Five, and HEXACO Emotionality is expected to show a negative correlation with Emotional Stability and a positive correlation with Agreeableness of the Big Five (Ashton & Lee, 2007).
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Please remember:
Academics began to publish Scientific Research using the HEXACO model of personality and they plan to discontinue the Big 5 model (a.k.a. Big Five or FFI five factor inventory) soon; because Big Five normative test had been proven/revealed as an incomplete and incorrect model to assess/measure personality of persons. 
I think, legally, online dating sites using the Big Five model of personality could be considered a FRAUD because they are using an incomplete model of personality. They are assessing 5 scales and not 6 scales.