Some of important info about the Character:

Clone Sonic "Tune-Up!" is the Main Mascot and Entertainer of Sonic Heroes Tera Pizzaomnia.
He unfortunately turns Evil at night, due to tampering of the Cloning Machine.
When he feels Silent's FEAR, he can change into Amok, because of the "delicious" smell!
Sonic "Tune-Up!" belongs to faction: Evil Empire... that Dr. Golden "Preparation" is on the lead.

Although, even Sonic "Tune-Up!" is on opposite side...
He likes Silent "The Player" and want to become hers Favorite Character Number 1.
They both, Silent and Sonic "Tune-Up!" especially like to tease each other.
The bond that connects them most is that:
The Game cannot function without the Player...
that's why he tries to keep Silent in imprisonment. Sonic "Tune-Up!" is the Game, Silent is the Player.

P.S. It's very late for me. Good night!