Wowaka, the Vocaloid producer and frontman for band Hitorie, has died at age 31. His tragic death was announced by the Hitorie record label website. It is revealed that he died in his sleep and the cause of death is acute heart failure.

The Hitorie tour was canceled in the wake of his death, according to the remaining band members — Igarashi, Yumao and Shinoda. The Japanese rock band was signed to Sony Music Group and released their first full-length project WONDER and WONDER in 2014.

The 31-year-old producer, singer, and guitarist died on Friday, April 5 due to heart failure.

Wowaka started off as a music producer using Vocaloid software. Although he stopped producing Vocaloid songs later in his career, his discography was put in an album called Unhappy Refrain. He developed a reputation with hit records such as Rolling Girl, World’s End Dancehall and Unknown Mother Goose.

Many fans left tributes to Wowaka, remembering his singing and musical abilities.

RIP wowaka, thanks for giving me amazing music with heartfelt lyrics. #wowakaさん

— kylo⁷ (@kylokis) April 8, 2019

wowakaP

Thank you very much, thank you.
I was shocked when heard the news and lost words. For me and of course many others, he’s a hero, a legend.

RIP wowakaさん

— Kapi (@Kapiten70) April 8, 2019

i can't believe wowaka died. i love his songs. god, rolling girl is so relatable?? and two-faced lovers was one of my first vocaloid songs. and i adore unhappy refrain!
rest in peace, wowaka. i will always remember you.

— sparky // dances to a upbeat tune (@KimasouS) April 8, 2019

Wowaka was last active on his Twitter and Instagram accounts on March 31.

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A post shared by wowaka (@wowaka_hitorie)

令和きれいだー。

— wowaka (@wowaka) April 1, 2019

Wowaka joined Hitorie in 2011 and he released multiple mini-albums and four full-length projects with the rock band. The late Vocaloid producer also performed a song named Polaris, which was the ending theme song for the Boruto: Naruto Next Generations anime.

Tearing up as I explained who #wowakaさん was to my husband. He was one of the many people whose lyrics really reached me in my darkest times as a teen. Seeing the Vocaloid community come together to show appreciation for him warms my heart. RIP wowaka

— tea mommy (@teaerine) April 8, 2019

Wowaka is remembered for his music – particularly his vocal ability and lyrics.