The main protagonist and the only male "D" in the world. He was a soldier in the NIFL as a 2nd Lieutenant before being sent to Midgar. Upon arriving in Midgar he is reunited with his younger sister Mitsuki after being separated three years ago and enrolled at Midgar. His dark matter fictional weapon is a gun.

In the "unlimited school battle action" story, the world was transformed by the sudden appearance of monsters known collectively as dragons. Before long, girls known as "D" were born with the dragons' powers. A boy named Yuu Mononobe is the world's only male "D," although his existence is kept secret. He is forced to enroll into Midgar, a school for "D" girls, where he see a female student Iris naked. Moreover, he is reunited with his long-separated little sister Mitsuki. 
 
(Source: Anime News Network)

__Height:__ 165 cm
__Agency:__ I'm Enterprise

[Profile](https://www.imenterprise.jp/profile.php?id=82) | [Anison](http://anison.info/data/person/31333.html)

A voice actor currently affiliated with I'm Enterprise. He was honored at the 6th Seiyu Awards as Best New Actor in 2012 and the 10th Seiyu Awards as Best Lead Actor in 2016.

**Non-Anime Roles:**
• Xiao (Genshin Impact)
• Ryker (Rune Factory 5)
• Vision Driver, Laser Raise Riser, and Suel (Kamen Rider Geats)
• Law (Tales Of Arise)

__Agency:__ I'm Enterprise

[I'm Enterprise Profile](http://www.imenterprise.jp/profile.php?id=44)

Married voice actor [Tasuku Hatanaka](https://anilist.co/staff/107018) in 2020.

__Non-anime roles:__
- Eunhwa - Goddess of Victory: Nikke (VG)
- Ether - Goddess of Victory: Nikke (VG)
- Belle - Zenless Zone Zero (VG)

Second Lieutenant Mononobe Yuu has been sent to Midgard, to attend the all-girl's school where his sister Mitsuki is the student council president. The school is specifically for people who have "D" powers, who are needed to fight dragons, and both Mitsuki and Yuu fit the criteria. On his arrival, he meets and befriends another classmate named Iris Freya, who is having difficulties with her "D"-related schoolwork. They will do their best to succeed in this dangerous world. 

(Source: MangaHelpers)

With the sudden appearance of the monsters that came to be called dragons, the world had completely changed. Before long, supernatural girls with the power of the dragons, called "D", were born within the human race. The secret existence of the only male "D", the boy Mononobe Yuu, was forcefully thrown into the school where the girls of "D" gathered - Midgard, where he saw the naked body of one of the students, Iris. Furthermore, upon meeting his long lost sister Mitsuki, Yuu seems to have been enrolled into this school...!? "When there's really no other choice, Iris, I will—kill you." "Can I really... believe you?" The curtains open as the "one and only story" about the boy who was supposed to become the strongest assassin and the poorly performing girl unfolds—! Unlimited School Battle Action!! 

(Source: Baka-Tsuki)