James
He and John meet Helen at Oxford, and it's the first time he's found a woman attractive in more than the abstract. It surprises him at first, but as the months go by, and the three of them settle into a friendship and a routine, he begins to wonder that he was ever surprised.
Helen is, after all, the most fascinating woman he's ever met. She's unrelentingly determined to be her own person, and yet she still has all the grace of any woman content to be what society demands she be. That, more than her beauty, is what catches and holds his attention.
Yet, he thinks he wouldn't find her nearly as interesting if he hadn't had John at his side, equally as interested — or perhaps more — in this most intriguing of women. After all, he'd met John first, and still finds him and the male form more attractive than the female (not that it's terribly safe to admit as such, but he'll not entirely hide it).
They draw others to them, and Nikola and Nigel make the dynamics of the group more complex than he'd anticipated at first, though soon enough it seems to settle out. It's a dance with it's own strange grace despite the complexity; some of that complexity brought by relationships that society wouldn't approve of — less, indeed, than they'd approve of what he and John shared before Oxford, and still do when they have the time to each other.
After the Source Blood, it changes again, and he finds himself drawn closer to Helen than to John, though he still finds she is the only woman he finds interesting enough to court (if he were so inclined to do such a thing, at least), and men are far more appealing. It makes it more interesting than perhaps it ought to be, and more so when they leave Oxford for London.
Yet he can ignore that, can ignore a number of little difficulties, until it's all too late for all three of them. They spin apart, and it takes time before he and Helen find a new balance with a new third into their lives. Again and again it occurs over the decades, though sometimes the dance is more complex, as Helen drifts from Britain, and he finds himself more and more bound to London.
They seem to settle again, to draw closer together, when Helen helps him to recruit a young man from special forces to the Sanctuary. She seems to find him as interesting as James does, if likely for different reasons, and she stays in London for a while (though she won't stay for terribly long; she has her own Sanctuary to look out for).
She comes to visit more often than she has in the past, and James doesn't think he can put that to the rise of aeroplanes or her purchase of a jet. Nor to the approaching limits of his mechanism, as she isn't aware of that. Even Declan, who is a constant presence, isn't aware of it. The only one who might be aware of the lifespan of the mechanism is hiding wherever he cares to hide, and James has no intention of seeking out Nikola to find a way to extend his lifespan further.
So it is Declan who's drawn her closer to him — and he to her — than they've been in decades. James doesn't, for once, question it, try to solve the puzzle of how and why, merely takes it as it is. It would worry Helen if she knew just how much he accepts it, but they're not nearly as close now as they were at Oxford or in the decade or so after, when it was he and her and John, and sometimes Nikola. So she doesn't know, and doesn't notice, and he can keep his secrets a few years yet.
James holds onto those secrets as jealously as he holds onto what he has with Helen and Declan, though he keeps the emotions as carefully disguised as the mechanism. Manuvering instead to coax Nikola back out into the open so Helen has someone to turn to (he could try to do the same with John, but he's looking for someone to provide her with a challenge and comfort, not someone for her to murder), and to ensure Declan's suited to take over the London Sanctuary.
It's an effort, and one he won't be able to know pays off, since it relies on his death for the last of it to pan out. All he can do is set the future in motion, and hope for as long as he can still think. Until the last moment, which he hadn't actually thought would be in a cave in the Himalayas, not until he's slumped against a column, listening to his oldest friends (friends, lovers, everything).
He doesn't tell them what he had in mind, doesn't admonish Nikola (or John) to look out for Helen or Declan. Only hopes that what he has done will be enough.
Nikola
He's watched them since Oxford, the intricate dance of affection and rivalry, love and anger, passion and regret. Sometimes he's joined in that same dance, though he never expects to be more than a temporary participant — nor, at times, terribly desires to be more than that. James is all edges and sharp sting too often for his tastes, and too perceptive besides. Helen he could adore for lifetimes, but he hates that he'll never be the only one she bestows her love on. Has hated it since he relized John had won her heart before he had a chance to make a move.
So he watches. He dances attendance on Helen — how can he not? — but tries not to let the love shine through. Joins James sometimes, when the latter searches for someone beyond Helen or John or a temporary companion. Fades into the background for years at a time, wrapped up in his own activities.
Watches John move in an eccentric elliptical orbit, coming too close when they're all drawn in to hunt down Adam Worth, and away again after. James and Helen circle each other ever more closely after, and even Nigel has to slip away from them, as he has, as John has. Though he thinks that Nigel will be the first of them to circle back, if not for the same reasons as Nikola or John.
The fourties drag them all close again, a chaotic dance that he can only see part of — John is too far out, and he's not allowed to leave the view of petty mortal men who fear him even as they need him. Nights spent too close and not close enough are all he has beyond the prying eyes of others. Wrapped in their embrace, though he knows he's only a temporary affection.
He slips away before they can — oh so gently, trying to be kind — push him away. Watches them, looses track of them as his own orbit, like John's, takes him both literally far from them as well as metaphorically.
It's almost the twentieth century before he thinks of returning to a closer orbit, like an electron losing energy, and slowly makes his way across the face of the world toward where last he saw them. Only to draw back again when he sees they have a third in their close dance. A human, yes, and more James' than Helen's, but still a third. And theirs is a dance that doesn't truly have room for four in any one figure. So he remains in the shadows, dancing a solo waltz like some photon emitted and not yet reabsorbed.
Only when he cannot resist the tug of his heart, of Helen's beauty, of the chance to disrupt the dance… only then does he return, bringing with him danger in his wake as easily as breathing. It annoys Helen, though she smiles; it endangers the human — Declan, he thinks he hears.
And it kills James, breaking the dance all to pieces, and even he cannot help but falter in his steps at this so-drastic change of the game, of the dynamic of the orbits of them all. The loss of Nigel hadn't done more than draw them close for a moment, and subdue them for a moment, but the loss of James, of one of the two primaries they've circled for so long… that change will disrupt them all. He can only hope he doesn't spiral out to roam in the cold alone, a planet flung free of its parent star.