|March 26, 2081|
|5'11" (180 cm)|
|Public Safety Bureau (former)|
|Tsunanori Sasayama (father) |
Mari Sasayama (sister)
Inspector Akane Tsunemori
|0106 Return of the Lunatic Prince (nightmare)|
0112 Devil's Crossroad (flashback)
Sasayama is a male of average height and a fit build in his 30's. He has brown eyes and short brown hair. He is typically seen wearing a black suit, white dress shirt, and red striped tie.
He is a misogynist with a short temper and prone to violence. He is also brash and careless, at times, making matters worse during investigations. However, Shinya Kogami says that in spite of that, he thinks Sasayama is an amusing person.
- One day after being abused by his father yet again, Sasayama fights back. When his father passes out, he thinks he has killed him. He goes to the police and turns himself in.
- During his rehabilitation, he decides to become an Enforcer. Ironically, after Sasayama turns himself in, his father wakes up and some time later rapes Sasayama's sister, Mari.
- After becoming an Enforcer, he is assigned to Division 01, led by Inspectors Shinya Kogami and Nobuchika Ginoza. Shortly after being assigned, Sasayama takes the two men to a club as a welcome party for Kogami, who has just been transferred to Division 01 as a new Inspector, but this only leads to trouble for himself.
- Some time after this, Division 01 is given a case to solve, later nicknamed The Specimen Case. Despite their best efforts, the team is unable to learn the identity of the murderer. Sasayama is the one who uncovers a lead and delves deeper into the case, eventually revealing that the person behind the murders is Shogo Makishima. His diligence leads to his own murder via plastination, wherein his body is dismembered, the parts re-arranged and immortalized in a clear, hard substance. Sasayama's gruesome death is the reason Kogami seeks revenge against Makishima.
Emergency Contact Information
Tokorozawa Protection Center and Rehabilitation Center A-326
Tsunanori Sasayama (relation: father)
March 2097 ‒ Graduates from Midorikawa Memorial Secondary School, Tokyo
February 2097 ‒ Enters Vocational School in Tokyo district, Major in Chemical Engineering
March 2100 ‒ Graduates from Vocational School in Tokyo district, Major in Chemical Engineering
April 2100 ‒ Enters Rehabilitation Center
September 2101 ‒ Leaves Rehabilitation Center
October 2101 ‒ Assiged to CID Division 01 as an Enforcer
October 2098 ‒ Hazardous Materials Officer's License
August 2099 ‒ Achieves Driver's License for Regular Motorcar Type I
Kogami and Sasayama are good friends and maintain a good working partnership as Inspector and Enforcer. Kogami says Sasayama is difficult to handle if he's in a bad mood, but he actually respects him and considers him to be an amazing man. Kogami also bows to Sasayama in apology after having a fight with the man. Sasayama replies that it's rare to see an Inspector apologize to an Enforcer, which mimics Akane Tsunemori's apology to Kogami. Sasayama's death causes Kogami's crime coefficient to rise to an unacceptable level, resulting in Kogami's demotion to Enforcer.
Ginoza and Sasayama appear to have a professional-only relationship. Sasayama sometimes calls Ginoza "Ginoza-sensei," although this is said as an insult, which Ginoza fails to realize. However, his death also affects Ginoza as it raises Kogami's crime coefficient to the point that he is demoted, upsetting Ginoza, as Kogami's friend.
Mari is Sasayama's sister. It is unknown how old she is when she dies, but Sasayama reveals that she committed suicide on the day Kogami and he find Toko Kirino in Ogishima. Sasayama believes that she killed herself because she was lonely after he became an Enforcer. And while he calls Mari his "beloved sister," he cannot bring himself to attend her funeral because he feels partly responsible for her death. 
Because she reminds Sasayama of his deceased sister Mari, he feels overprotective towards her which leads to him being taken off the case that eventually becomes The Specimen Case.
- His ID as an Enforcer is 00475-AYKT-45870-3.
- Before his death, he was designated as Hound 4 as an Enforcer.
- When Sasayama mentions, "the place that's closest to paradise in this world," during their trip to the "Pink Paradise," Kogami thinks it's a hospital, causing Sasayama to scold him as if it was a jinx.
- He is a martial artist with fighting styles in Silat and Jeet Kune Do. He influences Kogami into learning the martial art of Silat.
- The photo displayed in Kogami's room is the only photo of the friends together.
- He refuses to shoot female latent criminals, causing many missions to fail, which angers Kogami.
- He resembles Ryohei Sasagawa from Katekyo Hitman REBORN! because they share the same character designer.
- Main article: Mitsuru Sasayama/Image Gallery
|Joshu Kasei - Harumi Hosorogi|
|Akane Tsunemori - Mika Shimotsuki - Kiyoka Tedzuka - Yuan Kira - Fuse - Arata Shindo - Kei Mikhail Ignatov|
|Shinya Kogami - Tomomi Masaoka - Nobuchika Ginoza - Yayoi Kunizuka - Shusei Kagari - Mitsuru Sasayama - Sakuya Togane - Sho Hinakawa - Kaede Hasuike - Teppei Sugo - Kenta Yatsuka - Ryoichi Naito - Ryunosuke Hirako - Kazumichi Irie - Tenma Todoroki - Mao Kisaragi|
|Risa Aoyanagi - Mizue Shisui - Masawa Shimomura - Tetsuji Bando - Norimasa Inogashira|
|Ryogo Kozuki - Akira Yamatoya - Kasumi Senoo - Tochigi Morikubo - Kenji Inokuma - Shin Kanoe|
|Moe Suzuki - Shuichiro Domoto - Yoshitoshi Waku|
|Kaname Shinjo - Tetsuya Hyodo - Tsubaki Aikawa - Takayuki Haga - Koichi Hatano - Mai Momota - Ayaka Takami - Naoto Kurata - Hina Amari - Tsubasa Torii|
|Shion Karanomori - Joji Saiga - Maru|