Reol (れをる), born Kasumi Seki on November 9, 1993, in Nagano Prefecture, Japan, is a Japanese composer, utaite, and solo artist. She emerged from Japan's internet music scene, where she first drew attention by posting covers and original songs online. During that period, she combined internet vocal performance with composition and music production. Her music has been associated with j-pop, electropop, and singer-songwriter styles, and her solo releases have been linked to Victor Entertainment. She also performed "Kissaki (切っ先)", the ED of "Rurouni Kenshin".
In 2015, she formed the unit RΞOL with GigaP and Okiku. The project brought together composition, production, and performance, and it became a central part of her first professional stage. The group gave its final live concert in October 2017 and later dissolved because of creative differences.
After returning to her solo career, Reol continued working as an independent artist and composer. Her collaboration with GigaP and Okiku remained a key association from her early career, and the three continue to stay in contact while developing their own projects.
