Until You #RiakDadSiThan (Novel)

Saithan is the younger half of the pairing at the centre of this novel, and his name sits inside the book's own Thai title. He arrives in the story carrying a past he would rather not explain and a hard private rule about never being in anyone's debt. Sila is the older half: moneyed, self-possessed, accustomed to solving problems by paying for them, and no more willing to explain himself than Saithan is. A single night brings the two of them together, an obligation neither asked for keeps them in the same orbit afterwards, and the arrangement that grows out of it, labour traded against money owed, puts two proud men under one roof with nothing between them settled.

Where the television version smooths this into a slow, healing age-gap romance about trust rebuilt in daily instalments, the novel keeps the friction in. The relationship on the page holds love and hate in the same hand: combative, sharply conscious of who has the upper hand, full of moments where neither man will give an inch, and the Thai title, which reads literally as an instruction to call him Daddy, lands as a barbed joke rather than an endearment. Readers coming to the book after the series should expect a harder, more antagonistic version of the same two people, along with plot beats and a rhythm that the eight-episode adaptation rearranges considerably for the screen.

Until You #RiakDadSiThan (Thai: Until You #เรียกแด๊ดสิธาร) is a Thai boys' love novel by the author who publishes under the pen name CEO. It was released on November 1, 2021 by Deep Publishing, an imprint of Satapornbooks, running to 633 pages and roughly 197,000 words. An earlier serialized version, posted in twelve chapters, appeared on the webnovel platform Tunwalai under the same title before the book was collected. The finished novel is available as a single-volume e-book through mebmarket.com and as a print edition (ISBN 9786160043835) from Thai retailers including Naiin and Kinokuniya. It is the source material behind the 2026 Thai live-action drama Your Dear Daddy (เรียกแด๊ดสิธาร), written and directed by Rice Natid Kaveekornwong and starring Fluke Pusit Dittapisit and SaengNuea Jitaboon Ngamboonyarak, which makes the book the most direct way to see what the adaptation chose to keep, what it reordered, and what it deliberately softened on its way to television.