Aside from Conan Edogawa, another significant character in the series is Kogoro Mouri. Let’s explore the hidden truths surrounding this iconic private detective in “Detective Conan.”
1. Father of Ran Mouri
Kogoro Mouri is the father of Ran Mouri, who later becomes the love interest of Shinichi Kudo. Kogoro is fortunate to have a daughter like Ran. She is intelligent, independent, and often helps her father by organizing matters related to his detective work.

Ran possesses martial arts skills and is a member of the karate club at Teitan High School. She has also been trained well by her father in Judo, showcasing her proficiency in self-defense.
2. Separation from Eri
Kogoro was once romantically involved with Eri Kisaki before they decided to separate. After their split, Kogoro lived alone with his daughter, making the decision to live separately when Ran was only seven years old. However, the reasons for their split were never explicitly revealed. In reality, Kogoro and Eri have not officially divorced and still have feelings for each other.

Despite this, the exact reasons for their separation remain unclear. When she was younger, Ran often tried hard to reconcile her parents.
3. The Detective’s Personality
Kogoro’s character traits, such as being somewhat reckless and self-centered, contributed to Ran becoming an independent girl. Kogoro is known for being a brilliant detective with a somewhat laid-back personality.

Kogoro is also quite selective in his choice of clients. As a private investigator, he tends to prioritize cases involving attractive women, leading to potential conflicts with other clients. Fortunately, Ran is always quick to remind her father of his responsibilities.
However, Kogoro becomes quite serious when cases involve Eri and Ran.
4. Former Police Officer
Before deciding to open his own detective agency, Kogoro worked in the Tokyo Metropolitan Police Department with Inspector Megure. Although he is a clever man, Mori has struggled with investigations and gathering evidence. He also worked briefly under Inspector Yuminaga during his time in the police force.
During this period, Eri decided to separate from Kogoro and live independently for ten years for various reasons. One of them was related to Kogoro’s obsession with Eri, which made her feel trapped.
5. The “Sleeping Kogoro” Technique
Kogoro Mouri is famously known as “Sleeping Kogoro.” This nickname comes from his unique technique of solving cases while asleep.

In fact, this is merely a ruse created by Conan Edogawa, also known as Shinichi Kudo. Conan must continue to maintain his secret identity, which is why he often relies on Kogoro while solving cases.
Each time a case is solved, Conan uses a special pen to make Kogoro fall asleep, allowing the detective to unwittingly provide insights that lead to the resolution of the mysteries.
6. Kogoro’s Age in Different Versions
In the original “Detective Conan” series, Kogoro is introduced as being between 37 and 38 years old. However, this only applies to the Japanese version.
In the English version, Kogoro is said to be 43 years old. Nevertheless, it remains unclear if Eri’s age differs in this version. It is still a topic of debate whether her age will be significantly altered if it remains unchanged.
7. Voice Actors for Kogoro Mouri
The character Kogoro Mouri in the “Detective Conan” anime is voiced by two renowned voice actors. Initially, the voice actor for “Sleeping Kogoro” was Akira Kamiya.
Later, starting from episode 553, Rikiya Koyama took over this role.