
From the start, it had already remarked that there were two timelines. I'll further explain my theory from there. Let's say..
Timeline A: Itsuki published White Knight on Shonen Jump under her name, and Sasaki has not achieved his dreams of making it to Shonen Jump. In her childhood, she met a retired mangaka in the park, who, oddly had the same dream Sasaki had: "to create a manga that will make everyone happy". One day, the old man vanished leaving Itsuki with the robot the old man treasured.
Timeline B: Sasaki published White Knight on Shonen Jump under his name, leading Itsuki to question how they had the exact same plot. This lead to highschool Itsuki working under him as an assistant, and later working on Anima. To achieve White Knight, Sasaki plagiarized the original White Knight volumes that were spouting out of his broken microwave turned time machine. Keen detail, the same robot sat on top of the microwave.
Extra: What I struggle on is if the old man was the Sasaki who failed to achieve his dreams of being on Shonen Jump. But I found that to be impossible, because I think Sasaki of Timeline A would only be maybe around middle school. So, maybe it's just another man who had the same interests as Sasaki. ಠ_ಠ

Hah.. so you're telling me shameless bitch Rose is the Male Lead? And, from the spoilers written, Rose IS the Prince (from the future) who's trying to become Crown Princess. If so, does that mean someone else is in the Prince's body? Or is it just Older Prince (Rose) VS Younger Prince?
What is his motive to go back in the past though..?
You.. you almost got me there.. hnng.. (;´༎ٹ༎`)