Katekyou Hitman Reborn! Hidden Bullet

Written by Hideaki Koyasu and illustrated by Akira Amano, the novels were originally serialized in Jump Square.

Hidden Bullet 1: Mukuro's Illusions, and it was released on March 12, 2007.

Hidden Bullet 2: X-Fiamma, was released on February 4, 2008.

Hidden Bullet 3: Millefiore Panic, was published on July 3, 2009.

Hidden Bullet 4: The Funeral Flower Withers

Hidden Bullet 5: Simon Cooking!

[Wikipedia]