Shy-Ho-Shy
From Inkipedia, the Splatoon wiki
Shy-Ho-Shy was the Squid Sisters' producer. She was first mentioned in the booklet for Splatune as the committee member that originally discovered their talent. Shy-Ho-Shy produced the City of Color Demo as a reference for the Squid Sisters during the making of the song and might have been recorded while they were practicing it.
