Kuraudo Ooishi

Ōishi Kuraudo (大石 蔵人) is a character in. He is an old detective who works for the Okinomiya Police Station. For the past five years, he has been trying to prove that the Sonozaki family is behind the strange incidents that occur about the same time as the Watanagashi Festival, and has become increasingly persistent as his retirement draws close. He usually appears not long after the first murder occurs in a given arc, where he will ask driving questions to main character of the arc. The questions and his theories often fuel their building paranoia.

Background
Ōishi was born and raised in Okinomiya. His real father was killed when the plant he was working at was bombed during World War Two at Nagoya.

He did not get along with his father, but still missed him greatly. In the time after the war he was set to persecute people buying food illegally on the black market. There was a severe food shortage, and he was not proud of what he was doing. At that time he met a man who became like a second father to him. In the anime, he refers to this man as his father when it is revealed that the man was the manager of the dam construction project. During a fight provoked by his employees, whom he'd been scolding for drinking on site, the man lost control of his temper and viciously counter-attacked them. He was lynched and dismembered by those employees. He was considered the first of the annual victims of the curse, and Ōishi came to believe that the Sonozaki family, at the head of the anti-dam movement, were responsible for this.

Ōishi will stop at nothing to solve the serial murders, and believes the entire village to be in on it, with the Sonozaki family at the center. Due to this, he is hated by most of the village, particularly Mion, who firmly believes in her family's innocence. Even though Ōishi suspects the entire village as the culprits, ironically, the villagers themselves suspect that he could be the culprit, even going as far as calling him "Oyashiro-sama's servant". This is due to fact that Ōishi happened to come in contact with each of the victims of the curse shortly before their deaths, leading the villagers to believe that he chose them.

In arcs where we witness him going into retirement, he takes his elderly mother and they move back to the city of her youth. He has long wanted to fulfill this wish of hers. Most sources say this was in Hokkaido, one or two manga arcs specify it as Sapporo.

However, even after his retirement, he is still determined to find out the truth of the Great Hinamizawa Disaster, and together with Akasaka, he writes a book titled "Higurashi no Naku Koro ni" compiling all of the events that occurred in Hinamizawa, in hopes that the events would not be forgotten, and that they would one day be solved.

Appearance
Ōishi is a muscular, yet somewhat elderly man with short, grey hair and green eyes. Ōishi is rarely seen without a cigarette since he is a chain smoker. In Watanagashi-hen he even lights his cigarette in the hospital where Maebara Keiichi is treated at and even though Keiichi tells him that this is a non-smoking area he only opens the window to let the smoke out.

During his police duty he wears a cream-colored suit and a black collared-shirt with a red tie and suspenders. Due to the summer's heat, he doesn't wear his suit jacket, only keeps in his hand. In the visual novels, his shoes are dark brown but in the anime they are white. He also has a watch on his left hand.

Personality
Ōishi is initially portrayed as a fairly light-hearted, playful, and somewhat shady detective who is devoted and serious about solving the case, and at first seems to be a reliable ally to Keiichi. However, it is revealed in Tatarigoroshi-hen that he is capable of being extremely intimidating, and won't think twice about resorting to violence. His heavy determination about solving his case can also lead him to show signs of selfishness, such as when he attempted to use Keiichi's well being to help uncover the mystery in Watanagashi-hen. He is an avid fan of mahjongg and is occasionally seen playing with Keiichi. The victim of the first murder in Hinamizawa was a friend Ooishi often played mahjongg with and his death is what leads Ooishi to investigate the yearly murders.

Trivia

 * In Himatsubushi-hen, Ōishi tells Akasaka that ballroom dancing is a passion of his and that he likes it so much, he'll become a professional instructor before he turns eighty.
 * An interesting coincidence to note about Ōishi's name resembles the adjective oishii—meaning delicious—and is spelled the same as the Ōishi brandname of popular Asian snacks. This, combined with his plump figure and hearty laugh, has earned him the nickname of "Mr. Delicious" among Higurashi fans.
 * His first name, Kuraudo, can be written phonetically as "クラウド", cloud, therefore giving him his nickname.
 * Despite his appearance, he is quite skilled in wrestling and hand-to-hand combat. While maybe not so much as Akasaka, who is famous for his fight scenes, Ōishi was highly feared by many as a dangerous person who has never been defeated by anyone, bar the dam construction manager.
 * One of Ōishi's main weapons is a gun, and even though he seems skilled with one, he admits in Himatsubushi-hen that he has actually never used a gun before, much less even raised or pointed one at somebody.
 * The brand of the cigarette which Ōishi smokes is Gaster. "Gaster" is the imitation of Caster, a real cigarette brand produced in Japan.
 * Despite appearing in nearly all of the original sound novels, Ōishi has one of the lowest numbers of individual sprites, and unlike all of the other characters, his sprites are not denoted by moods, but simply as "oisi1," "oisi2," and so on.