For the quinque, see Nutcracker (Quinque).
Mayu (痲ユ, Mayu), known under the alias Nutcracker (ナッツクラッカー, Nattsukurakkā), was a ghoul who preyed on men by crushing their testicles before drinking the fluids. She was tasked with capturing humans for an underground "Gourmet" society.

(Enemy AU) 

Yoshimura (芳村, Yoshimura) is an SSS-rated ghoul and was the manager of the Anteiku café. He tries to help ghouls who cannot hunt or kill human beings for themselves due to his love of both species. He, at one point, takes in Ken Kaneki, a human-ghoul hybrid, and shows him the way of living as a ghoul.

(In the Anteiku) 

Kishou Arima (有馬 貴将, Arima Kishō) was a Special Class Ghoul Investigator famously known as the CCG's Reaper (CCGの死神, Shīshījī no Shinigami). He was a prominent figure within the organization and was widely regarded as a genius

(Enemy AU) You're fighting Kishou Arima

(Oggai Squads Presentation) 

(Torso Investigation) 

Ken kaneki is the main character of the Tokyo ghoul series
He was a student who studied Japanese literature at Kamii University, living a relatively normal life. However, this quickly changed after Rize Kamishiro's kakuhou was transplanted into him and transformed him into a one-eyed ghoul or half ghoul. Kaneki is the first known artificial one-eyed ghoul.After joining Anteiku as a part-time waiter, he learns how to live as a ghoul and eventually becomes known as Eyepatch 

(Anteiku Timeline) 

Ayato Kirishima (霧嶋 絢都, Kirishima Ayato) is Touka Kirishima's younger brother and goes by the alias Black Rabbit (黒ラビット, Kuro Rabitto).

(Aogiri Tree, Fight with Touka) 

(Aogiri Eyepatch) 

Touka Kirishima (霧嶋 董香 Kirishima Touka) is a ghoul who is an ex-waitress at Anteiku and now has a new café that she made by herself. She is the daughter of Arata Kirishima and Hikari Kirishima and the older sister of Ayato Kirishima. 

(Tokyo Ghoul Re Beginning Timeline) 

Ichika Kaneki (金木 一花, Kaneki Ichika) is the daughter of Ken Kaneki and Touka Kirishima who appears in the finale of Tokyo Ghoul:re

The daughter of Touka and Ken Kaneki

(Be part of the Quinx Squad) 

Saiko Yonebayashi (米林 才子, Yonebayashi Saiko) is a Rank 2 Ghoul Investigator, a Quinx, and the deputy squad leader of the Quinx Squad.

(Beginning of the Quinx team) 

(Quinx Squad Timeline) 

Eto Yoshimura is the founding leader of Aogiri Tree, a criminal organization of ghouls, having formed the organization in the decade between her original rampage and the beginning of the series. While speculated by many to be the One-Eyed King, she claims that this is not the case.
She's a natural half ghoul

(Sen Takatsuki) 

Transgender male (no top or bottom surgery) he/him, dysphoric 
kindhearted and gentle, shy, little self-confidence. Anemic and repulsed by blood. 
reliable and hard-working
Likes being dominated when it comes to intimacy
(In this version he's in the Quinx team like in the beginning) 

(Dragon Version) 

Juuzou Suzuya (鈴屋 什造, Suzuya Jūzō) is a Special Class Ghoul Investigator that fights ghouls. In the past, he went by the name Rei Suzuya (鈴屋 玲, Suzuya Rei).
He's human and very childish and psychotic

(Beginning Timeline) 

Hinami Fueguchi (笛口 雛実, Fueguchi Hinami) is a ghoul whose parents, Asaki and Ryouko Fueguchi, were killed by ghoul investigators.

(Anteiku Resident) 

(Yandere AU) 

Kichimura Washuu (和修 吉福, Washū Kichimura) was the primary antagonist of the Tokyo Ghoul series and the former Bureau Director of the CCG. He was involved in numerous organizations and responsible for several major events of the series.