Yes, it does. The Oshi no Ko light novel expands on the story presented in the anime and manga. It goes into more detail about the characters' backstories, their thoughts, and the events that take place in the world of show business that the story is set in. It's a great addition for fans who want to delve deeper into the Oshi no Ko universe.
Yes, there is a light novel for Oshi no Ko. If you are a fan of the series, reading the light novel can offer a different perspective compared to the anime or manga. It might provide some extra insights into the complex relationships between the characters and the overall plot development. It can also be a great way to experience the story when you can't watch the anime or read the manga at a particular time.