Reisuke Houjou
Reisuke Houjou (豊穣 礼佑)(Roman Pantheon Member, Mercury) is the Fifth diary owner and the youngest of the twelve. Ostensibly appearing as a harmless five-year old, Reisuke is a master strategist and forces Amano Yukiteru and Gasai Yuno into a deadly match in Yuki's own house. He is often accompanied with a pair of hand puppets, and owns the "Hyper Vision Diary".