Haruko Nagaya Celebrates Marriage After Longtime Romance—Exclusive Eyewitness Report
Her husband is affectionately called the “Delusional Prince” or simply “Prince”, with a devoted fan following
“I’m very sorry to share personal news, but I would like to announce that I have officially married Masato Kanai.”
On September 20, Haruko Nagaya (30), vocalist and guitarist of the four-member band Ryokushoku Shakai, announced her marriage to Masato Kanai (40), vocalist of the accomplished rock band BIGMAMA, on the band’s official website. Kanai also announced the marriage through his band’s official site.
“Ryokushoku Shakai, which made its major debut in 2018, rose to popularity among young audiences with the drama theme song sabotage for G-senjou no Anata to Watashi (TBS, October 2019) and the ending theme ‘Shout Baby’ for the fourth season, second cour of the anime My Hero Academia (NTV, January 2020).
Their 2020 release ‘Mela!’ became a mega-hit, surpassing 400 million streams. From 2022, the band appeared at the NHK Kōhaku Uta Gassen for three consecutive years, and in 2023, they won the Excellent Work Award at the 65th Japan Record Awards for ‘Summertime Cinderella,’ making them one of Japan’s leading mixed-gender bands,” said a music magazine writer.
On the other hand, BIGMAMA, formed in 2001, is a five-member rock band incorporating a violin. Kanai, who writes and composes the songs, earned the nickname “Delusional Prince” from fans for the romantic lyrics of their fourth single Diamond Ring, which intertwines a solar eclipse with a lovers’ reunion. Since then, he has been affectionately called “Prince” and has gained a passionate following.
Kanai is also known for writing lyrics for other artists. Notably, he penned My Friends Forever, the coupling song to LiSA’s hit theme Homura for the 2020 film Demon Slayer: Mugen Train.
The couple first met when Nagaya participated in BIGMAMA’s song LEMONADE, released at the end of 2019. Kanai was captivated by her singing and personally invited her to collaborate, making the partnership a reality.
“I’m captivated by Nagaya-san.”
LEMONADE is a duet centered on the joy of love. In the song, Nagaya sings the line “I LOVE YOU” with her clear, transparent voice over Kanai’s lyrics. In an interview with the entertainment-focused media outlet SPICE (December 20, 2019), Nagaya explained why she participated in the song:
“I really love the lyrics. From a female perspective, it’s incredibly joyful.”
Kanai, in turn, praised Nagaya’s voice:
“She was ideal. Not overly distinctive, but not plain either. Very straightforward and flexible. If you liken it to yogurt, it’s not a flavored type, just the pure, basic kind. The essence is delicious on its own, and everyone inevitably comes back to that flavor.”
He further added:
“During rehearsals without Nagaya-san, BIGMAMA experienced serious Haruko withdrawal.
It was really intense (laughs). I had to do something about it. Everyone was captivated by Nagaya-san.”
Even at that time, Nagaya was clearly special to Kanai—not just as a vocalist, but as a woman. The magazine later witnessed their affectionate behavior in early October 2020.
At a convenience store in Meguro Ward, the two were picking out ice cream. Nagaya, wearing a hairband, stayed close to Kanai, who asked, “Which one should we get?” After buying their ice cream and leaving the store, the couple—both in T-shirts, perhaps feeling cold—quickly headed to Kanai’s nearby luxury apartment.
Five years later, they reached the milestone of marriage. In her wedding announcement, Nagaya expressed gratitude to fans:
“I hope to give back to everyone through music, and I will continue to strive even harder both as an individual and as a creator of music. I would be grateful for your warm support. Thank you for your continued support.”
A new collaborative work from the couple may not be far off.
