"Pay attention to me, aniki," says a wispy voice from above, shortly followed by the sound of a book clattering to the ground.
Seijuro pays it no mind, gracefully turning another page in his textbook. "Tetsuya, it's late. Don't make too much noise."
A pouty huff echoes through the room and a misty blue figure appears in the far corner, clouded in a mysterious fog. The figure is of a boy, not any younger than Seijuro himself, with soft features and a prominent though half-hearted glare. He folds his semi-transparent arms and stares at the back of Seijuro's head.
As far back as Seijuro could remember, he's had this companion by his side. They often played together as children, and treated one another as siblings. Seijuro hadn't seen anything out of the ordinary with his ghostly brother, but his parents had. They'd been worried as they explained that having an imaginary friend for so long was unhealthy, and that was when he realized his parents couldn't see Tetsuya. He'd felt pretty stupid at the time, not once realizing that they'd never set a dinner plate for him, nor had they ever spoken to or about him.
He'd wanted to scream that Tetsuya wasn't imaginary, but even as a child he knew that would only make the situation worse. So, he pretended to not see Tetsuya while his parents were around. The little ghost had been initially affronted at being blatantly ignored, but eventually he grew used to the routine and only made himself known when they were alone.
When Shiori fell ill, she'd been lying in bed half-conscious when she suddenly gripped Seijuro's arm in a tight vice. With wide and frantic eyes, she'd pointed right toward where Tetsuya was quietly hovering and demanded to know who he was. The ghost had been stunned into silence, and Seijuro introduced him to her. She'd nearly fainted upon hearing his name, and years after her death he still didn't understand what the exchange had meant.
However, he accidentally stumbled across the answer while looking through old family files with his father. Seeing the name 'Tetsuya' written on the documents prompted him to pause and not-suspiciously ask who it was. And, for once, Masaomi didn't ridicule him for asking questions.
Shiori had given birth to twins, the first being Seijuro and the second being Tetsuya. While Seijuro had been born healthy, Tetsuya had not been so fortunate. He had inherited his mother's constitution to an almost exaggerated degree, and hadn't been breathing upon birth. The prolonged oxygen loss sent him into a downward spiral that had him dead within 24 hours. Shiori had grieved the loss so intensely she'd simply refused to acknowledge his existence at all, eventually convincing herself the boy really had never been born.
Even Masaomi seemed shaken up while explaining the situation, and Seijuro for the first time felt some semblance of sympathy toward him.
He decided not to tell him about Tetsuya's ghost.
When he confronted Tetsuya himself about the situation, though, he admitted he'd known the story from the beginning. Seijuro tried his hardest to be mad at him for withholding such information, but he just couldn't. Tetsuya had been there when no one else had been; For Shiori's funeral, for when Masaomi pushed him just a bit too far, and he'd even saved him from his own personality shift. He could never be mad at his brother for all that he'd done for him. Instead he sighed, and quietly requested Tetsuya call him 'aniki'. He was met with enthusiastic agreement.
And now, with the knowledge of their relationship as twins out in the open, Tetsuya's become a lot more outspoken.
"Aniki~ Don't you know because I died as a newborn I'm stuck with the needs of one? I'll die without attention."
"Tetsuya, you are already dead."
"Yes, but...I can still go to the ether. You know, second-death and all that."
Seijuro sighs and puts his pencil down. "If you stop knocking my books off the shelves, I'll come cuddle you."
The ghost perks up almost immediately and Seijuro can't help the fond smile that appears on his face. It seems even incorporeal beings enjoy hugs. Tetsuya settles himself down, and one of his wisps reaches out to place the books he'd already pushed over back where he'd gotten them. Seijuro raises an eyebrow as he settles into bed.
"Have you ever considered that you are basically a ghost cat?"
Tetsuya gives him a considering look and molds the mist over his head into two triangular ears. He stares at Seijuro with wide eyes. "How do I look?"
"Adorable as always. Come on, now, before I remember any more tests I need to study for."
"Aniki is very hardworking," Tetsuya declares as he moves into the invited space next to Seijuro. "His peers seem to be under the impression he's naturally perfect at everything he does, but actually he spends all of his free time studying. He is very admirable, but he shouldn't push himself so hard. It's unhealthy."
Seijuro hums as he straightens the sheets around them, reaching over to turn off his bedside light. "An astute observation, but unless I push myself my grades will slip and you know what would happen next."
Tetsuya sighs, exhaling a cold gust of fog that dissipates into the air. "I wish I could help you more."
"I know you do, but it's not necessary. I have been under worse pressure in the past."
The ghost buries his face into Seijuro's chest. "Not fair. I want to be useful to aniki but because I'm dead I can't do anything."
Seijuro frowns and pulls him away. "Is that what you think? That you are of no use to me?" Tetsuya nods hesitantly and his gaze softens a bit. "Do you really not know? You've already done more for me than anyone else in the world has. It might not be studies or the like, but I would not hesitate to say you are the only one I can put absolutely all of my trust into."
Tetsuya still looks unsure, so he continues.
"Back then, in Teiko, I was so sure everything was going to fall apart around me. I...I said and did some awful things during that time, but no matter how badly I treated you, you always came back. You always called me aniki, and you always threw my stuff around to demand my attention." Tetsuya smiles at that. "You were there for me even when I felt completely alone, and that is the only reason I was able to come back to myself. I can never thank you enough for what you've done. So..." Seijuro looks stern, but his expression wavers as though he's having difficulty keeping his face in check. "Please don't ever feel like you can't do anything for me, because you already have."
Tetsuya looks guilty as he nods, looking away just slightly. The corner of Seijuro's mouth quirks upward.
"Besides that, I should probably give you double the credit since you've done more in your afterlife than most people do in their actual life."
The ghost looks up at him with a grin, the sparkle finally returning to his eyes. "You're right. Do you know how difficult it is to get around without a body? Everything falls right through me if I don't concentrate. I'm like a colander, except instead of holding noodles I just let them all fall into the sink."
Seijuro chuckles. "So, just pouring the pot into the sink with nothing to catch them?"
"Exactly like that."
He laughs, and Tetsuya snuggles further into his body. He's cold and sends electric shocks through his body wherever they meet, but that has never bothered him before. He pulls his younger twin closer and pets his hair, sending wisps of mist straight into his pillow. "I know you don't need to, but do try to sleep. It makes me nervous to see you awake all the time."
Tetsuya's laughter is muffled, and his smile widens.
Suddenly, something occurs to him.
"Hey, why do you suppose it is that I can see you and no one else can?"
A pause. Tetsuya unburies his face with a contemplative look.
"I...never thought about it before. I don't do anything special to show myself to you, you've just always seen me."
Seijuro blinks. "Does that mean I'm a medium?"
Tetsuya stares at him for a moment before snorting. "Are you going to get your own show now where you hire people to act like you're spot-on with your readings? Because you have to look the part if you're going to do that. You know, tacky nails, too much hairspray. The works."
Seijuro wrinkles his nose. "No thank you."
His brother snickers. "Seijuro Caputo."
A pillow hits him in the face, and Tetsuya gasps in mock outrage.
Seijuro rolls over with a childish grin, and allows the tension to seep from his body all at once.
He might be a pain sometimes, but he wouldn't trade his twin for the world.
"Or you could be like Whoopi Goldberg in that movie. Seijuro Goldberg?"