The Music Theory Behind Why Rihanna's "Sex With Me" Is So Sexy

It's not big or clever to say that Rihanna and her music are sexy. One would only need to browse the sartorial tour-de-force of her music videos to understand her sex-symbol status, before even getting started on the musical content. Aside from her voice, which is as satisfying-yet-tantalising as the smell of freshly ground coffee, there's the tang of the accent that makes you feel like you're rolling in warm sand on the shores of Barbados while a Teletubby sun beats down and you're fed rum on a drip.

As if all of this wasn't enough, the deluxe edition of 2016's ANTI graced us with one of the best bonus tracks of all time: "Sex With Me". It's absolutely saturated with sex, and not solely lyrically, vocally, or because it's performed by a beautiful and iconic sex symbol. Sex is intrinsic to the very skeleton of the track. Inconveniently, you stray into problematic territory when arguing in favour of the existence of inherent sexuality in music. The feminist musicologist Susan McClary has faced substantial criticism for her output on the subject. But, because you can construct an argument in line with much "new musicology" that, for example, Beethoven's forceful hammering of a fortepiano is the musical equivalent of banging someone really hard, I'm going to run with the idea and apply it to Rihanna. Here, the lyrics thrust with sexiness as the song's intent, while the track's actual harmony reinforces that. The result? One of the sexiest songs ever written.

Now, for the theory. Most pop music appeals harmonically to humanity's consistent desire for familiarity by using the same four chords – a fact that literally any self-respecting Music Snob will repeat very loudly at a party whose playlist is deemed disappointing for its lack of Justin Vernon (spoiler alert: he uses them too). Most conventional pop songs written on the "Western" seven-note scale make frequent use of the chords IV, V and I (with "I" referring to chord number one, built upon the first note of the scale, "II" to number two, built upon the second note, and so on. Chord I is the root chord or tonic, synonymous with the overall 'key' of the song, and, in Western music, usually serves as something to work towards harmonically). Not only are these three of the chords that are easy for our ears to digest, but using a V-I or IV-I sequence creates a feeling of completion and satisfaction, bringing us back to the song's root in the most convincing possible way.

"Sex With Me" doesn't really stretch beyond the realms of conventional harmony; nor, even, is it beyond the chords used commonly in pop and R&B (it's worth noting that it's distinctly R&B over pop, using chord II, a jazz derivative, where straight pop might use IV). However, the lack of definitive harmonic resolution – the sense that a note or chord doesn't leave you hanging, but instead guides you through the comfort of a "complete" sequence – complements the song's message so well that we're left in no doubt that sex with Rihanna is definitely "so amazing". And it does that by basically distinguishing itself as the 'Tristan chord' of 2016. The Tristan chord, thanks for asking, is the most iconic motif from Wagner's opera Tristan und Isolde, which, put simply, uses the 'tritone' interval (literally three tones, or an augmented fourth) to create tension. It thus uncomfortably postpones a transition to chord V. The relationship between music and lyric in Wagner could be – and is – the topic of several lengthy volumes in itself, but here it's just worth mentioning that Wagner uses the Tristan chord's chromaticism – in translation, using 'wrong' notes that sit outside the piece's key – and delayed resolution, to both create and represent sexual tension. Essentially, we feel the emotion of the drama – in this case, yearning – in the music itself.

The crucial difference between Wagner and Rihanna (alongside the main other ones which are that, as far as we know, Rihanna doesn't have a fetish for rose-scented satin, and Wagner never rolled a joint on the bald head of his bodyguard) is that the characters of Tristan and Isolde themselves feel the yearning with us, whereas Rihanna is perfectly content to tease and tantalise and just keep us in the loop about how great it would be to have sex with her, which she knows we will literally never do.

Interestingly, contemporary pop often slightly contradicts the "major key = happy / minor key = sad" rule that you're taught in Year 9 Music to become "major = happy / major also = sad / minor = sexy". Rihanna subverts again here by using E major – a vibrant, sunny key – as her tonal centre, complementing her own contentment, confidence and ease. Most of the song fluctuates between chord I (E major) and II (F sharp minor), with melodic hints at chord V (B major). Despite being identifiable, these chords are still tinged with uncertainty: chord I adds a major 7th, which shimmers in a high register, an excruciating semitone away from what's known as the tonic (in this case, the note E: the first note of the scale, and the one that defines the song's key), hinting all the time at proper resolution. "Sex With Me" does not, like most pop and R&B tracks, have a prominent bass line – it is syncopated and sporadic. For obvious reasons, a bass note can ground and satisfy us, but here our ears are drawn to the tonic that appears in a higher register. As well as decisively not satisfying us, this device (unexpected chord voicings are prevalent throughout the song) also creates the intrigue that distinguishes it from your more 'basic' pop banger.

The vocal melody is what cements this track as a true medal-winner in the 'contemporary pop songs that make you want to have sex via their harmonic workings' category, that also includes "Drunk In Love" (textbook harmonic-minor-sexy), "Wild Thoughts" (both-Latin-and-electric-guitar-sexy), and "Dangerous Woman" (crammed-with-satisfying-cadences-sexy, ie. the opposite of "Sex With Me"). It does not fully assert the harmony by hitting the notes of the relevant chords; rather, it hovers above them and occasionally dips in, giving us just not quite enough. Suspension in this sense is a technique often used by Drake; his first "One Dance" entry – "Grips on your legs" – is a typical contemporary R&B suspension, very similar to Rihanna's "I know I know, I make it hard to let go".

"One Dance" is nowhere near as consistently unresolved as "Sex With Me", and even "Sex With Me" does not dodge the bullet entirely: there are melodic hints at chord V (which can make us feel the most fulfilled) which serve to reinforce the lyrical content of the song. Arguably the most fulfilling moment is "oooh-wee aw yeah" in the first verse, a chord V teaser moment. "Sex with me is amazing, with her it'll feel alright" similarly uses more of the "right" notes harmonically than the majority of the vocal. These extracts are not only lyrically significant (the former in its portrayal of satisfaction, the latter in its assuredness) and come at structurally important moments in the song – but also convey the idea that, since the vocal is the only harmonic resolution we are offered, the only means of achieving fulfilment is Rihanna herself.

The song's raison d'etre is reinstated so powerfully by its harmonic and melodic makeup that it becomes a force to be reckoned with. In this sense, it's her finest work. At least until I figure out the chords to all her other songs and realise that music can be intrinsically umbrella-like, too.

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