A thousand years ago, the divine general Fei Peng and the Demon Sovereign Chong Lou engaged in a fierce battle in the New Immortal Realm. The divine sword "Zhao Dan" fell to the mortal world, and Fei Peng was demoted to earth. A millennium later, the Lock Demon Tower of Shu Mountain trembled, and Fei Peng's reincarnation, Jing Tian, who obtained the demonic sword, embarked on an adventure alongside Tang Xuejian, Xu Changqing, and Zi Xuan to collect the Five Spirit Orbs and seal the Lock Demon Tower.

In the distant future, Kagami Village is a suburban mountain village that has been left behind by the highly developed science and technology in urban areas. "If you're not well behaved, a look-alike will come." Higure Akane, a middle school student living in this village where an old legend still remains, was looking forward to being reunited with her older sister Higure Sui, who has been released from the hospital after a year. However, shortly after her sister's release from the hospital, Akane receives a phone call. "The person in that house is not your older sister."

In Cinnamoroll's origin story, a white dog flew down from the skies one day and was discovered by a female Cafe Cinnamon worker. The "I.Cinnamoroll" brand depicts an alternate world that poses a what-if question: What if Cinnamoroll had not met the Cafe Cinnamon worker on that fateful day? The "I" in the title stands for both the English first-person pronoun "I" and the Japanese word "ai" (love), and it represents the brand's theme of taking care of one's own body and mind.