Disclaimer: This is a work of fiction. All characters, terms, and affiliates of Gintama are not mine, but belong to their respective owners, Hideaki Sorachi, Shueisha, Sunrise, TV Tokyo, VIZ Media &c.
A/N: I don't remember much about how Kagura and her dad interacted, but it seemed to fit.
Letters
In the rare moments where she sat down and sat still, Kagura wrote letters back home. When asked why she didn't just email her family—it was certainly faster, you know?—she just shrugged and said, "Because papa has to have something to read when he gets back."
So she wrote undisturbed, her childlike writing crooked in its sincerity as she scribbled her adventures across the page. He never tried to read what she wrote, but he was sure the great Umibouzu was being regaled with tales of sukonbu and a "crazy, missile launcher carrying bastard." He'd heard her mumble the words herself, her pen flying across the paper as she went.
In even rarer moments, Kagura would finish her tome-like letter, stare at the envelope she just barely managed to close, and cock her arm back, aiming for the window. It was only then that he'd interfere, coming from behind the couch, hand on her wrist.
"He'll write back," he'd say into her hair, because while instinct told him what to say, it still fled in the face of a trembling lip. Her surrender to his pressure on her wrist was always gratifying and damning. She could out muscle him in her sleep, so as he felt the tension leave her arm, he told himself that her belief in him was worth the little lie he fed her when she was in a mood.
Her dad would never write back.
Gintoki pressed a finger against her cheek as she looked back up at him.
"Now let's go mail that letter."