|Eye Color||Light Brown|
|Manga Debut||Line 9; Plan B|
|Anime Debut||Episode 5; Monster|
|English VA||James Marler|
Yuichi Utsumi (内海 佑一 Utsumi Yūichi ) is a cameraman who works at a video production company stream and is in charge of weather forecast relay. During a live weather-broadcast, his human reporter co-worker Yuriko Hyuga, was stabbed by Ren Murakami. Upon seeing her blood, Utsumi transformed and uncontrollably started to suck her blood. This incident was the first stage of the "Ikebukuro Incident".
Utsumi is an adult man with a pale complexion and dark circles under his eyes due to being an initial non-blood-drinking devil. He has very short, slightly spiked brown hair and small pupils with light-brown eyes. He also appeared to wear a beanie and a jacket.
He was seen being happy with his job, and appeared to work well with Yuriko Hyuga before the incident. Like most other devils, however, he lost control of himself when seeing blood and started sucking Yuriko's blood.
On a snowy evening, Utsumi along with his co-workers, including Yuriko Hyuga, were holding a live-weather broadcast. Just before the end of the broadcast, Ren Murakami rushed to Yuriko and sliced her throat with a kitchen knife. Seeing blood, Utsumi transformed and attacked Yuriko and drank her blood as the camera rolled on. He drank so much that Yuriko was about to die, but Johannes Kleeman interfered by knocking him out and later proceeded to ask people to call for medical attention to both Utsumi and Yuriko.
During the incident, the crowd and all of those watching at home were witnessing proof that devils really exist. This incident came to be known as the "Ikebukuro Incident", staged by the CCC for the purpose of making people aware that devils really do exist and to increase anti-devils protest. A live-weather broadcast was the perfect opportunity to trigger devils across Tokyo to transform and therefore make humans open their eyes.
Following the incident, Utsumi was arrested for bloodsucking.