Orenchi no Furo Jijou Wiki
Kanji 龍己
Romaji Tatsumi
Other names Big Brother (by Goromaru)
Biographical Information
Birthday Unknown
Age 17[1]
Zodiac Unknown
Family Unnamed Grandfather
Hisatora (uncle)
Kasumi (younger sister)
Unnamed Cousin
Status Alive
Physical and Vital Statistics
Gender Male
Heigt 172 cm
Weight Unknown
Anime Episode 1
Manga Chapter 1
Voice Actors
Japanese Nobunaga Shimazaki

Tatsumi (龍己 Tatsumi) is the main character of the series, a teenage boy who found Wakasa lying close to the river and is now taking care of him in his own house.[2]


Tatsumi has messy black hair and tired golden eyes. He is tall and is shown to have a quite muscular body, managing to taking down a grown man with only a few movements.[3]


Tatsumi is a kind, selfless guy, who isn't particularly concerned about his new free-loader. Although he isn't happy about the larger water and gas bills, he is a frugal and knows it's not cheap keeping a merman supplied with fresh, warm water. He is very concerned about finances and seems sullen and disinterested, but he actually cares about his new friends.

Usually he will entertain his guests and teach them about the human things they don't understand, but sometimes he's the one who has to reel them back in and snip their (usually Wakasa's) dreams before things get too out of hand.


As a child, Tatsumi spent a lot of time in his grandfather's house and after he died, he stayed to live in the house because it was close to his school.

When he was around ten, Tatsumi fell into a river while he was fishing. He was then rescued by Wakasa, who after being offended by Tatsumi, he threatened him so he will not tell anyone about his existence.[4] This made Tatsumi to hate the water, taking baths and mainly, the slime.

Years later, Tatsumi found Wakasa stranded near a river by the upstream dam and thinking he was hurt, he took Wakasa with him to his house. At the time, Tatsumi didn't seem to remember him and was shocked to find out he was a merman, but decided to let him stay in his bathtub anyway.[2]


  • His hair freaks out in humidity.
  • He has a bad back from often sleeping in the bathroom.
  • He is often reminded of sea food dishes when around Wakasa and friends.
  • His favorite food is steamed crab, second being octopus.
  • He has great upper body strength.
  • Wakasa's scales often stick to his clothing.
  • He works at his cousin's liquor store.[5]
  • He is popular among older women.
  • He occasionally breaks the third wall.
  • He hates slime.
  • His name come from the "Kuzuryu" river.



  1. Chapter 38
  2. 2.0 2.1 Chapter 1
  3. Chapter 42
  4. Chapter 60
  5. Chapter 43