Masaki Taniguchi (谷口 正樹, Taniguchi Masaki) is a reoccuring character in the Boogiepop Series. He is a middle-school student, the non-blood-related younger brother of Nagi Kirima, and the lover of Aya Orihata.


Masaki is a friendly and kind young man. Unlike his sister, he doesn't show strangers any unwarranted aggression, judging by how he readily welcomed Kazuko Suema into his home despite not knowing who she was. After transferring to his middle school in Japan, he quickly became very popular with all of the girls, although he didn't enjoy their company at all, as he could sense their shallowness. Because of his popularity, Masaki became hated by basically every boy in his school. Despite having similar fighting prowess to his sister, he never fought any of his angry schoolmates, as he didn't want any trouble, instead only wishing for normal school life. The situation with his male classmates improved, though, once Shinjirou Anou told everybody that the only reason he hated Masaki was because he was jealous. Hearing this, many of the others realized that themselves, and stopped trying to hurt Masaki. Masaki was also the object of Shinjirou Anou's love, although the boy never seemed to realize it.

Despite his constant female attention, the only girl Masaki fell for was Aya Orihata, who he quickly became infatuated with. Masaki risked his life multiple times for her, and was the first person to show her affection, which made the girl also fall for him. Even after finding out she was acting on orders when she spent time with her, he quickly recovered and ran to save her.


Masaki is a young man with short brown hair and brown eyes. He is often seen wearing his middle school unifrom, consisting of a pair of black pants, a gakuran, and a white shirt., or casual clothing, including a blue sweater over a white V-neck T-shirt and green pants.


After Seiichi Kirima's death, his wife, Kyouko, and their daughter, Nagi, moved overseas, and Kyouko remarried, taking the surname Taniguchi. The man she married already had a child, which was Masaki. Nagi was the only one to keep the Kirima surname, out of respect for her father.

While living overseas, in Phnom Penh, Masaki trained in martial arts under a man named Gen Sakakibara, who, despite having some very unconventional teaching methods, turned Masaki into a very capable and powerful fighter, although he still wasn't able to stand a chance to his big sister.


Boogiepop and Others

When Kazuko Suema visited Nagi Kirima's house, in order to asked her about the situation she witnessed the day before, involving Kyouko Kinoshita, she noticed that the nameplate had the name "Taniguchi" on it, instead of Kirima. Then, she was welcomed at the door by Masaki, who invited her in to talk with Nagi, and explained that she was his big sister.

Boogiepop Returns VS Imaginator Part 1

Boogiepop Returns VS Imaginator Part 2

Boogiepop Countdown

Boogiepop Wicked

Boogiepop Bounding

Boogiepop Antithese


  • Masaki's last name, Taniguchi, means "mouth of the valley".
  • Masaki's first name is written with the characters for "justice" and "tree".