Ya-ya-yah ga Yattekuru!

In the Taishou era, there was a girl named Kinako who loved to sing. However, her parents forbid her to sing, and forced her into an engagement! While running away from her engagement, she fainted. During the time she was unconscious, she traveled through time. She wakes up and finds herself in the modern age, where she is confronted by a group of rising idols?!
(Source: MangaUpdates)