Shinichi Saeki (佐伯真一, Saeki Shin'ichi) is the director of Saeki's Cosmetic Surgery Clinic and a member of the Hakata Tonkotsu Ramens baseball team. He runs a mortuary in the back of his clinic and often assists his teammates with various underground jobs.
Saeki is noted to have earnest, gentle eyes that match his personality. He wears glasses and has short black hair worn in a part.
He is mild-mannered and has a habit of talking politely to people regardless of whether they are younger or older, in stark contrast to his job as a cleaner. He is fan of baseball and a member of the Tonkotsu Nine, and in games he frequently hits foul balls along the first base line.
Mayor Harada Scandal Arc
Saeki is introduced while treating Xianming Lin after he is stabbed by Hisashi Ivanov. Later, Banba visits him wishing to buy a dead body, and Saeki performs cosmetic surgery on Shota Yamazaki's severed head to make it look like Banba's. Kazuki Saitoh also makes use of Saeki's services when he decides to have plastic surgery performed to disguise himself, and the recruitment poster for the Tonkotsu Ramens pinned to the bulletin board in the clinic's waiting room inspires him to join the team.
After the events of the first novel, Saeki carpools to a practice game in Jiro's car and plays baseball along with the rest of the Tonkotsu Nine.
Niwaka Samurai Impersonator Arc
Saeki joins the Ramens in a practice game, where Genzo's suggestion of a punishment game pushes the team to put their all into their final offense. Saeki hits a foul ball, but the other team's umpire calls it fair, and the first baseman makes an out. Two weeks later, he provides José Martínez with the body of a young man of roughly the same build as Lin. The corpse tricks Abe and Yamamoto into believing the Niwaka Samurai's stand-in has been tortured to death. Martínez takes the real Lin to Saeki's clinic, where the doctor treats his wounds. After Lin wakes up, Saeki receives a call from Genzo and confirms that Lin is alive.
The next day, Enokida brings Yamamoto to the clinic, and Saeki performs surgery on him to make Yamamoto look identical to Saitoh.
Shou Wang Arc
Saeki misses the team's weekly practice, but a month after the end of the story, he joins the rest of the team at the fireworks festival in early September.
Saeki has a request for one of Genzo's killers, and Lin gets the job. In the past six months, Saeki has received the corpses of five homeless men from an unknown sender. The corpses have been brutally beaten and stabbed but show no sign of bondage, and Saeki notes that their front teeth have been unprofessionally pulled. He is confused by the methods of killing and disposal and is unnerved upon discovering that none of his clients are acquainted with the sender and that a courier has been threatened during their disposal. He asks Lin to find and kill the culprit, though with only photos of their badly beaten and disfigured faces, the job will a difficult one.
The day after tasking Lin with finding the culprit, Saeki receives the body of Manabu Kuroiwa, and he calls Lin to his clinic to let him examine the body and give him Kuroiwa's possessions.
Saeki removes the bullet and stiches up Jiro's arm after he is shot by members of the Mutagawa Group. He invites Jiro to stay the night and helps him into bed after he collapses from exhaustion and the effects of the pain medicine. Saeki remains in the clinic through the night working on a corpse until Jiro wakes up the following afternoon.