That is the "magical spell" passed down from grandmother.

One particular summer, Yoshino (main character：Renameable), a 17-year-old girl, follows a butterfly through the main gate.

Beyond the gate, she finds herself in Taisho Era red-light district of Yoshiwara, where the cherry blossoms are in full bloom.

There she encounters Harufumi, a young writer, and Kocho, a male geisha.
Yoshino tries to find her way back to modern times while searching through the Yoshiwara district, where the nights are wild and rowdy ......

More details on the official game page of Yumemidori Nostalgia ...