I can't really explain things well but I hope you get the AU. I just needed to type it out.
It started a few days ago when I was talking to a friend on Skype about the game Professor Layton and their endings and how they were well made. While doing that I had a davejade moment with the third game ending and I just. AHHHH
( I tried not to include the whole story of the game in here but idk eve;; )
Basically Dave would be Layton and Jade would be Claire and since Dave was the Knight of Time I thought it kind of fit. So how I imagined it was that Dave and Jade had just met again after an "incident" that happened a few years back. But during the time between the incident happening and them meeting again, Dave became all famous with his SBAHJ Movies and music such as Layton because a well known Professor with his puzzles. 10 years had passed and they meet each other again but Jade claims to be her "sister", Julie, and together they both go on this Crazy movie scandal hunt with his assistant, Lil Cal (Or Dirk, which ever you'd prefer.) After some epic rap battles and they find out that Gamzee was the one who was behind all that mess, whatever it was, and they solve everything