SHAREDOL combines two concepts chosen from roughly 15 proposals submitted by young producers at Toei Animation and Sotsu. The Toei group suggested a story about a modern-day ordinary young man who time-travels to a realm blending the Edo period with the near future, forging his own fate. Meanwhile, the Sotsu group proposed an idol who goes back in time to the Edo era. This led to the creation of a pilot film centered on the themes of "Edo" and "Idol."
The narrative of SHAREDOL takes place during the Edo period's Kansei era (1789–1800), a time when entertainment faced severe restrictions. Operating on the premise "What if contemporary idol expertise were applied to develop Edo girls?" it portrays the idol endeavors of girls grappling with personal issues. The protagonist manages six girls—a teahouse girl, a samurai girl, a Dutch trading house girl, a merchant girl, an oiran (high-ranking courtesan), and a kunoichi (female ninja)—each leading distinct lives.