KAFU (可不)

Overview

KAFU (可不, Kafu) is a CeVIO AI song voice based on the singing voice of virtual singer KAF (花譜) and the first character in the "Musical Isotope Project" run by KAMITSUBAKI STUDIO. Her genre is classified as Vocaloid-style.

Career history

KAFU was announced at KAF's second one-man live, "Fukakai Ni Q1," as a collaboration with the CeVIO AI voice synthesis software. Character design was handled by PALOW., who also designed KAF. She has white hair, a white outfit with geometric patterns, and a hair ornament made of triangles.

After the announcement, three in-development voices were previewed and a voice survey was held. Voice "A," closest to KAF's own, took 65% of votes, but KAF wished that "KAFU be KAFU and KAF be KAF, similar but a different existence," so the younger-sounding "B" was officially adopted. Originally planned for winter 2020, the release was delayed twice and finally came out on July 7, 2021.

At the V.I.P STREAMING COVER LIVE "Marshmallow Live," a song voice for Dreamtonics' Synthesizer V AI was announced. It was scheduled for January 15, 2024, but was postponed on December 23, 2023, and officially cancelled on January 19, 2025.

Since July 7, 2022 (the first anniversary), the four-panel manga "Isotope Observation Diary," featuring the Musical Isotopes including KAFU, has been published regularly by illustrator and manga artist Kemuri Nakamori.

Recent releases include "初期二階堂（前期）" and "初期二階堂（後期）" (May 28, 2025), "これが恋なんだな" (May 31, 2025), "SORAMO" (June 16, 2025), "BestDX2.0" (November 20, 2025), "Memorial Ghost" (December 17, 2025) and "Kotoba" (February 8, 2026).

Concept and character

The name comes from the initials of "possibility" (可能性) and "incomprehensible" (不可解); "KAFU" combines "KAF" from KAF's name with the U of "YOU." The concept is "From KAF to KAFU, from listening to creating." Producer PIEDPIPER described her as "similar to KAF but a completely different existence." There are no official age, height or weight settings, while the unofficial idea that she loves curry udon is widely accepted.

Musical style

Built on KAF's singing voice yet given a younger timbre, KAFU is a synthesized voice designed not only for listening but for creating music.