Ibaraki Prefecture (茨城県・Ibaraki-ken) is a prefecture of Japan located in the Kantō region of Honshu. Rena and her parents had moved to this prefecture when she was younger in favor of her mother's career, but after their divorce and Rena's subsequent mental breakdown, she and her father move back to Hinamizawa, a year prior to the main story. Incidentally, it is also revealed to be Detective Minai Tomoe's residence before she is transferred to Kakiuchi City, and as a result, she is indirectly involved in the aftermath of Rena's assault on her male classmates, and becomes entangled in the dark mysteries of Hinamizawa in Tokihogushi-hen.

It is never clearly mentioned where in Ibaraki the Ryūgū family lived, but as Tomoe's jurisdiction in Ibaraki was later revealed to be the capital city Mito (水戸市・Mito-shi), it may be assumed the Ryūgū family stayed there as well.

Mrs. Ryūgū is described to be a very talented lady and this aptitude was quite apparent in her career growth. After going independent as a fashion designer along with her colleagues, including her husband, Mrs. Ryūgū received an opportunity to work at a prestigious design firm in Ibaraki prefecture. Despite this meaning that she would have to move away from Shishibone City, and sacrifice her husband's job in the process, the Ryūgū family mutually agreed to the transfer.

Mr. Ryūgū assumes the role of a caretaker while their daughter Reina (now known as Rena) is admitted to a school in Ibaraki. With Rena's mother often working late, Mr. Ryūgū and Rena were left in care of the household chores, which they enjoyed doing together, encouraging them to bond as parent and child. Rena describes her initial time in Ibaraki to be satisfactory, yet somewhat bittersweet, due to the frequent absence of her mother. As Rena's mother became more successful, she began to spend more time at work and social events. She also frequently took Rena on expensive outings, sometimes alone, and sometimes with her friends from work. It was on such an occasion that Rena meets Mr. Akihito, the man her mother would later divorce her father for.

On a certain day, when Mrs. Ryūgū had taken Rena to a particularly expensive restaurant, she reveals to her daughter that she plans on leaving Mr. Ryūgū and marrying Mr. Akihito. She invites a dumbfounded Rena to join them on their new life together. Rena is distraught and questions the morality of her mother's illicit affair, but Mrs. Ryūgū declares she has no choice now, as she was pregnant.

The divorce proceedings commence rather bitterly as Mrs. Ryūgū refuses to communicate with her husband and navigates the case through her lawyer. The divorce deeply distresses Mr. Ryūgū, who initially lashes out at his daughter in grief for not telling him about her mother's lover, despite having met the man. Rena is wounded by her father's reaction and her mother's adultery, and she later rejects Mrs. Ryūgū and renounces all ties to her.

Soon afterwards, Rena gradually descends into insanity, having to deal with the aftermath of her mother's betrayal. She continuously blames herself for not rejecting Mr. Akihito or discouraging his friendship with her mother, and begins to exhibit aggressive behavior. Rena's accumulating stress and frustration takes a toll on her mental health and she begins to show symptoms of the Hinamizawa Syndrome soon after.

At this point, Rena was implied to be already at L3. According to the police, an unforeseen incident at Rena's school in Ibaraki culminated in her violently acting out and assaulting three of her male classmates with a metal bat. One of the victims was beaten so badly that he later sustained permanent damage in one eye. After the assault, Rena's persistent fury caused her to smash all the windows in the school building until she was restrained by some of the school teachers and staff.

Rena is admitted to a psychiatric ward, where she receives treatment and counselling for her condition. In the midst of a nervous breakdown at the facility, Rena indulges in lethal self-harm and attempts suicide. It is at this point, when she encounters a "presence", which she recognizes as Oyashiro-sama. This presence informs her that her misfortune was a result of violating the ancient village customs and that she must return to Hinamizawa if she wanted everything to go back to normal. Rena takes this advice to heart and tries to tell everyone around her that she needed to move back to the village. Rena's psychiatrist decides this may prove to be a fruitful rehabilitation measure and thus, Rena and her father move back to Hinamizawa to start their life anew in 1982.

Coming Soon.