Hairu Ilhei

Hairu Ilhei was a Investigator Ghoul and the main antagonist of Tokyo Ghoul Re.

Before
Very little is known about Ilhei's past life besides her having possessive relationship with Arima. And she had a formal education. She has also been trained in combat enough to begin working with Investigator Ghoul at 16 years of age. And at some point she was even assigned to Arima Squad.

Owl Suppresion Operation
Ilhei seemed like a member of Zero Squad.

Auction
Ilhei appeared as a member of Zero Squad, she cornered Hinami and assisted in her captured.

Rose Extermination
She fought on the side of the Quinx Squad. She also fought alongside Taishi Fuera, Shiki Kijima and Nimura Furuta. She then fights Matsumae, she managed to hit her in the belly a few times. However, Matsumae escaped her when Kijima captured Yuuma who was one of his accomplices. Then she and the other Investigators Ghoul fought Matsumae, Mairo and several Tsukiyama family ghouls. And when Ilhei saw Matsumae's kagune-shaped sword, she desired to obtain it as her quinque. And during the fight, she demanded that she subordinates give her often fiften T-Human against Matsumae, but Mairo appeared and protected with koukaku shield, Mairo jumped on the women, and beheaded her before that. Ilhei had a memory of when she was young with Arima.

Trivia
Ilhei before introducing into the story and the anime/manga, she still gaped as one of the hooded limbs in chapter 31.