There are also some self - published works or online stories. You can search on platforms like Wattpad or Archive of Our Own. Just be aware that the quality may vary. On Archive of Our Own, you can use tags like 'age difference' and 'gay relationship' to narrow down your search and potentially find stories that fit the 'gay daddy twink' concept.
One popular book that might have relevant stories is 'Call Me by Your Name'. It beautifully portrays a relationship between an older man and a younger one. Another could be 'Maurice' which also delves into same - sex relationships with an age difference. However, the exact 'gay daddy twink' dynamic might be more subtly presented in these literary works.
I'm not sure if there are books specifically titled 'gay daddy twink story' in a very direct sense. But you could look into queer literature anthologies. For example, 'The Penguin Book of Gay Short Stories' which may contain stories that touch on relationships between older and younger gay men. These anthologies often gather a variety of works that can give you a sense of different relationship dynamics within the gay community.