That's where his mind screeched to a halt with the sheer wrongness of it.
But "Aunt" Melody and "Grandpa" Boyan, even with that conspicuous gap in the family tree, worked for them. And so it was for years, with the girls growing astonishingly quickly, with Melody living at home despite being married, with Boyan the happy patriarch of their little family unit, that things just worked.
Even so, he never truly felt like "Grandpa." He was too young. The girls were too old. And Melody was still his little girl, the daughter Boyan all too happily continued to love and support as if she were far younger than her true age.
And then she left to live with her husband.
And even then, it had never really registered with Boyan. Even throughout her pregnancy-- Melody was still that same child, just with a bigger tummy. And as time passed, as she grew larger, as they learned she would be having twins, as he even tried to contemplate being a grandfather, none of it seemed REAL to him.
The reality of the situation crashed on him before he even had time to blink.
There had been so many people present for the birth of the twins; people Boyan, at this point, couldn't even remember. Doctors, nurses, family... And when the time came for Melody to request the epidural (Just as she'd planned), she had shooed everyone out, save for the ones administering it, and her father. And he knelt on the floor and held her stooped shoulders, stroking her hair as, for the only time that night, she burst into tears and confided just how terrified she was. Not just of the process of receiving an epidural (though the initial injection to numb the site caused a panic so intense that Boyan could scarcely keep HIMSELF from crying out in fear), but giving birth, of raising children, of her life suddenly, drastically, permanently changing, of no longer being that little girl who could simply run into daddy's arms whenever she needed.
It was so easy for Boyan to forget that she was a grown woman, about to be a mother. He'd shushed her just as he had when she came to him as a child, trembling from a nightmare or sobbing with a skinned knee, and kissed her forehead and told her that everything was going to be okay, that he'd make sure of it, and then--
--And then before he knew it, he was being ushered from the room.
Even knowing it was coming; that the actual moment his grandchildren were born would be one for Melody and her husband alone, it still came as such a profound shock that he had been rendered speechless. And right there, outside the delivery room, where Boyan stood, staring at the door in a near-stupor, that chapter of Melody's life, of Boyan's life, came to an abrupt close.
He didn't remember how much time passed before he was once again allowed in that room. Before he could see his tired daughter, her ecstatic husband, and the two babies in her arms. It was all such a blur then. He remembered hearing that her son had resembled Boyan, of all people. He remembered taking little Eiji into his arms, brushing a finger over his delicate cheek, the pang of joy he felt when Eiji opened one golden eye and saw his grandfather's face for the very first time...
And then how Eiji's face blurred as a whirlwind of emotions-- of pride, of joy, of excitement, of love, of anguish as he realized that the days of his children being so utterly dependent on him like the babies were so utterly dependent on Melody and Boyue were long behind him-- gripped his chest so tightly he, at first, felt he couldn't even breathe.
And when his daughter, his lovelybeautiful, grown daughter asked him why he was crying, how Boyan couldn't answer. Not because he didn't wish to, not because he couldn't speak his thoughts eloquently enough to properly match the importance of the event, not because he didn't wish to upset his daughter..
...But because he, so completely overwhelmed with emotion, was physically and mentally incapable.
These were his grandchildren. He was a grandfather. In the blink of an eye, his world had been turned upside-down. And no matter how desperately he wished, he would never be able to go back.
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(Melody, Eiji, Tsubaki, Hitsuga)
Hitsuga visits Melody and the twins in the hospital while she's recovering from labor.