Kengo Eritate

Kengo Eritate (襟立 健吾 Eritate Kengo?) is an independent rock guitarist and vocalist from Tokyo who lied about coming from Osaka out of shyness. Although he formed a band called IKEMENS (イケメンズ Ikemenzu?), other members got tired of his character and dropped out. After that, he makes Wataru and Shizuka join and aims at the major debut as a new IKEMENS as part of his lifelong dream to be a rockstar. Though he learns that Wataru's lifelong dream is not like his, Kengo remains Wataru's friend as the two promise to help each other out with their dreams. However, when nearly devoured by the Rhinoceros Fangire, Kengo encounters Kiva and begins to idolize him and then Keisuke after seeing him fight the Ladybug Fangire, wishing to be the latter's apprentice. When he is deputized as a temporary Fangire Hunter, Kengo has to be hospitalized after shoulder and hand injuries from fighting the Crab Fangire.

Once released from the hospital, he learns that due to his injuries, he can no longer play the guitar, and as a result, gets angry at Wataru from hiding this truth from him. The rage gets worse when Kengo overhears Nago naming Wataru his apprentice instead of him, with Kengo being taken Shima's wing and made into an official Fangire Hunter, now bitter and harsh with no respect for Nago and very distrustful of Wataru. He even went so far as to cut and dye his hair back to black, along with discarding the Kansai accent he used to maintain the charade of being from Osaka. When Nago is injured in action, Kengo eagerly takes his place as the Ixa System's user. However due to the incident where Kiva's Fangire nature takes over, Kengo is forced to return the Ixa System back to Nago after he attempted to redeem himself by fighting the Seamoon Fangire and almost getting killed by the Bishop. Kengo, in a last-ditch effort to bring back Wataru to battle, plays his guitar with what ability he has left and then begs Wataru to come back, apologizing for his recent behavior and coming clean about why he behaved like he did recently. It was not that much because of Wataru hiding the fact that he could no longer play the guitar from him, but that he needed to blame someone for his own weakness - he was actually relieved that he could no longer play the guitar as he eventually knew that he has little talent in music, but could not live with himself as someone who gave up on his dreams. At first, Wataru initially refuses, stating that he cannot be friends with anyone due to his heritage, but after Wataru returns to being Kiva, he relents and both he and Kengo become friends again. He later is a guest in Nago's wedding and helped carry the presents to the wedding.