You and your brother have always considered yourselves two halves of the same whole, a set. Your rhythms have always been his rhythms, your moods his moods.

The place where Phineas lives is technically your own home, too, but you hardly can call visiting somewhere for a half hour tops whenever the mood strikes "living" there. Nonetheless, you have a key, so you never have to knock or call. He's there when you want him to be, always welcoming, always happy to see you. He never dumps his problems on you, never demands anything from you. He hardly talks anymore. Just smiles his genuine smile and moves how you want him to.

Just how it's supposed to be. Just how it's always been.

When the two of you were younger, Phineas was the one to set the rhythm. Adolescence was his domain, after all. He knew just what the two of you would do every day; he could usually know what you would like, what your opinion would be, without asking you, though he always asked anyway. Your hands were gripping the tools you'd need before he was done with the blueprints.

That kept on even through puberty, through the era of you sneaking out regularly to meet girls, to meet boys, to meet others. They were something for your body, for your mind. Never your heart. No girlfriend, no almost-boyfriend, no regular lay could take your heart, since it's hardly even yours. It has always belonged to the single being that is you and Phineas, and you could never rip it in half, even if you wanted to. They weren't even a blip on your radar, and it didn't seem to even touch Phineas' world. Thoughts of flesh and tongues and friction became strange and silly and impossible the moment you entered the room you shared with him. You were back to building things, inventing.

That is, until you got bored.

Breaking the sanctuary of your room was the first thing you did. You brought people there when Phineas was out. There was this thrill deep in your chest, curling in your stomach, sinking through to your legs. A feeling of completely wrongness, of every moral fiber in you screaming no, no, stop and yes, brilliant, keep at it, all at the same time.

That, of course, wore off in time as well. It lost all excitement, all thrill. You had to think hard about the wrongness, about the danger, even when you were stark naked with some stranger pinned under you in Phineas' own bed. Even talking yourself up about it only produced a dull twang in your throat, scrapes on your heart.

That's when you took the reins, coaxed them out of Phineas' hands and into your own. You suppose you switched up your roles. You started making the plans, the blueprints. You knew them by heart by now. Any Phineas had – has, still – the tools. His smile, his eyes, his mouth, his hands, his entire body. He began building and shaping and bending himself to your liking.

It started very simple, practically innocent. He'd never been one for touching, really, so you started touching him a little more, grabbing his wrist or his hands to pull him along instead of trusting him to come, making sure your hands touched when something was passed between the two of you. It was practically unconscious.

That slid into sitting closer and closer whenever you could, to rubbing circles on his wrists and hands, to laying your hand on his hip or thigh, to rubbing circles there as well.

Suddenly, somehow, that ended up becoming kissing. He could laugh off the touching, make fun of you for getting more "touchy-feely," could rationalize it. There was nothing to rationalize about your mouth against his. So he didn't rationalize. Didn't argue. Let you kiss him. It was like passing the salt at dinner, like waking him if you woke up early. It was something you did that didn't even need to be discussed, that just happened. As close as you and Phineas have always been, it was the natural course of action.

Speaking of natural courses of action. Of course, the innocence of your kisses didn't last very long.

As said, Phineas was never one for touching. After all those years living together, sleeping practically side-by-side, you never felt more of him than a hug, and nothing not initiated by him. All of a sudden, all of his body was yours, lying before you like unclaimed land. You could rub his back, grip his hips, comb your fingers through his hair.

You never had to consciously think about it. How Phineas was your brother. How Phineas was so inexperienced compared to you. How Phineas probably had some sort of reason why he had never done any of the things you did with him before. These thoughts stayed front and center at all times, turning your stomach, making your hands shake.

Phineas doesn't remind you of any brotherly feelings the two of you have always had. Phineas doesn't tell you about any aversions or reasons he hasn't reciprocated the feelings of half the tri-state area practically falling at his feet. In fact, Phineas never mentions what the two of you do in your bed, ever.

Most importantly, Phineas never tells you to stop.

Your makeouts had gotten to near-sex levels heavy by the time you met your next girlfriend. You'd never been a cheater, and she was a smart young woman; she wanted to wait a while before getting too physical with you, and you completely respected her for that. So you'd rolled back to chaste kisses – mostly on her round, gorgeous cheeks – and hand-holding.

Phineas didn't seem to miss that physical intimacy with you, and he took a liking to her right away. He's always known more about you than anyone else, but now he knew even more. You got to watch him hold this knowledge with the grace and class you've always expected from him. There were no slips, no suggestive glints in his eyes, not even an edge to his aura. He was entirely gracious about being replaced, so quickly and easily.

But it wasn't quick or easy. And he was not replaced.

You searched for reasons to break up with her that weren't brutish. There weren't many. Eventually, she ended up breaking up with you. You had Phineas on your lap ten minutes after she left.

Things cycled and circled. Another girlfriend. Phineas. Boyfriend. New boyfriend. Phineas. Strings of lays and flings and one-time dates to nowhere near your bed. Phineas, ever virginal, in between. Girlfriend. Very interesting boyfriend.

After a few dates, he told you he was asexual, but perfectly fine with you seeing other people for the more physical love he wasn't going to give you. He was very wonderful, and you thought he was a keeper. You two even kept going for longer than your usual, but he and Phineas seemed to be getting far too close for comfort. Phineas and he would talk the way neither spoke to you, with a very strong sense of understanding between the two of them. And he touched Phineas in ways he avoided touching you, hands on his knees or foreheads pressed together, like it meant something different between the two of them than it meant between you and him.

It wasn't even jealousy. You never felt such a thing about their relationship because it was so obviously different. It was, however – and this you knew with your whole heart – a protective reflex, something deep in your brain chemistry that told you that Phineas was yours and you were Phineas' and your boyfriend could very easily take him away from you, on one level or another. So you chased him off.

You found yourself just in time, because the next time you kissed Phineas, you felt hesitance. You felt his hands flitting around, half trying to find a proper place and half deciding if he wanted to push you away.

He didn't push you away.

He's never pushed you away.

Even when your makeouts clumsily stumbled into sex.

Taking Phineas' virginity was the most overwhelmingly wonderful and the most horrible, painful thing you've ever done. Your body was going crazy with joy and lust and disgust. You half wanted him to tell you no, to make you stop. You half weren't sure if you could stop. You entirely felt like you were at a viewing, staring at the corpse of someone you loved in a coffin, everything so fake and so ugly and so sad. You entirely felt like you were doing something you were always meant to do.

It got easier every time.

People have always treated Phineas like some sort of otherworldly being, some creature above mere mortal humans. You've never understood it. Phineas is just a boy. Phineas is just your brother.

Phineas is just a name that slips out of your mouth like blasphemies slip out of the mouths of others. Phineas is just a pair of eyes, with emotions that you change from dull happiness (the most detestable thing) to something, different, darker, and blanker, with just a few choice words or a look, let alone a touch. Phineas is just a body that moves how you want it to, when you want it to.

When college came around, the two of you had every possible place practically begging for you to come to their school. Phineas laughed and told you to choose for the both of you. Phineas elbowed the major and minor-choosing and the scheduling to you with a sheepish smile and something about how he just couldn't pick what he wanted to do more.

Of course the two of you were dorm mates. Of course the two of you landed almost every possible class together. Of course Phineas graduated slightly higher than you, since you were a little too busy with side projects and college flings and maybe getting a little drunk every once in a while.

You got a final, solid girlfriend. You didn't stop anything with Phineas. It didn't even feel like cheating, with him.

You married her. The first thing you did after the wedding was become an adulterer, but only with Phineas. And that certainly hasn't stopped.

If Phineas has any special opinion regarding that, he hasn't volunteered it.

Jobs have been gained and left together, maybe working in different departments but on the same things. It's been enough to legitimize the two of you keeping an apartment together, with him living there at all times and you bouncing between him and your lovely wife.

But it's thinned out. You only come every once in a while, when you feel like it. And you don't come to work with him, or to visit, or to chat. You come for one thing, and you get it without a word and then leave without a word.

You're not quite sure what he does when you're not there. You're not quite sure you care.

When you walk into the apartment today, you find him sitting on the floor of the bedroom. He's staring at a book without reading it, something he's always done when he wants to think. You're surprised he didn't hear you come in.

You gently touch his head. He doesn't move. You take off your shirt and throw it on top of the book. He moves. It's more of a shudder than a surprised jump. He pauses and then turns, smiling at you. You half help, half yank him up to his feet. He hugs you. You kiss his neck and he stops hugging you. He stops doing anything you don't make him do.

You don't watch him undress. You hardly look at him anymore. You know every line of his body like you used to know every whim in his heart, every wish in his head.

Your hearts used to beat to the same rhythm. Now your bodies move to that rhythm instead. It's the same thing, you think. Better, in fact.

Before you leave, you kiss him. He doesn't kiss back, doesn't respond at all. He lies on the bed like a ragdoll, expressionless and immobile. You taste vomit in his mouth.

It's almost like you don't have Phineas anymore, haven't had him for a long time. All you have is the scraps of a boy who was something like your brother and something like your best friend and something like your soul mate.

"I'll see you soon? Next week?"

He seems surprised by your voice. His eyes move to you, but he otherwise remains still.

He looks at you for a while, unseeing. You want to hear his voice, just a little. You haven't heard it in a long, long time.

He rolls over, curling into himself, facing away from you.

"Yeah," he says. "Yeah."