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When Byakuya Ishigami returns home from space, he feels he’s prepared himself for anything. Surprising a teenager by coming home from somewhere without warning tended to not go well, however with Senkuu his issue wasn’t wild parties. No, instead of destroying the house with some party there was a 70% chance Senkuu had destroyed at least part of the house with an experiment gone wrong. He had prepared himself for all possibilities, everything between not a spec out of place and a pile of ash with a note simply reading that he was staying with Taiju.
He should’ve known there was no way to predict every one of Senkuu’s actions. Because he had absolutely not prepared for the strangely familiar man with dual-colored hair laying across his son’s lap and listening intently while Senkuu rambled and worked over him nodding and humming to him in affirmation. Senkuu was rambling about his plans for his journey into space and Byakuya himself could barely understand half the words that were being said, yet the man was still nodding as if he understood and looking at Senkuu as if he had already completed the ship and gone to space to hang the stars himself. Unless his son had managed to find another teenage super genius, this kid was totally bullshitting. Senkuu has obviously picked up on this too as he stopped rambling.
“Oi, Mentalist did you get any of that?”
The man laughed, “is that question even necessary Senkuu-chan~?”
“I guess not,” Senkuu chuckled back, “you did look like you were thinking though what ya got?”
“Well, the whole homemade rocket thing is impressive don’t get me wrong, but your birthday past a while ago, you’re eighteen can’t you just apply to get JAXA to send you out there? You have the connections.”
“That’s ten billion percent not gonna happen. Even if they decide to send another person up soon, you’re missing the biggest piece.”
“What?”
A small lovesick smile passed across Senkuu’s face, a face that before this moment Byakuya would swear the boy could never even make, as he said something so sappy, so illogical, so not Senkuu, that he was convinced this Senkuu was a failed clone of some sort, “you, stupid. What would I do in space without my mentalist?... of course, I’d also be bringing Taiju and Yuzurihara along with us too.”
The following stunned silence from the other man allowed Byakuya to remember the fact that he had forgotten to speak due to shock of the rare tenderness of the moment. His brain failed to provide him anything to stay to make this less awkward, so he simply cleared his throat to announce his presence.
The now red-faced mystery man composed himself quickly and looked to him, then to Senkuu, then finally to the hanging pictures of the two of them together years back. He opened his mouth to speak, but was quickly cut off.
“No text, old man? You’ve been back for a couple days.”
“I was gonna surprise you since we came back early and I figured you wouldn’t be watching the TV. Clearly I was wrong.”
“I wasn’t. The big oaf spoiled your surprise, though I guess this ass had a hand in it too for turning Yuzurihara into a huge Lillian fan.” Senkuu said, turning Byakuya’s attention back to the stranger in his house, who at least had the decency to move himself off his son’s lap by this point.
“And who is this ‘mentalist’ that’s so important you’d delay your trip to space for?”
This time, it was Senkuu’s turn to go red as the stranger answered for him, “Asagiri Gen, Senkuu-chan’s dear friend~”
Suddenly with the name the odd familiarity clicked, “my son, is friends... with Asagiri Gen... a magician...?”
“Oh? You’re familiar w—?”
“Just friends? That’s cold Gen.” Senku fake pouted nudging him with his shoulder. “Let’s do this again properly before he never shuts up, old man, this is my boyfriend Asagiri Gen, yes he is that Asagiri Gen, Gen this is Byakuya Ishigami. Got it? Good. Now can I get back to my work?”