I Reincarnated as an Extra and Latched Onto the Heroine

Jiang Nainai never imagined she would transmigrate into a book! And all because she got curious and clicked on a link! Jiang Nainai: This is ridiculous. But if she had to transmigrate, why did she end up as some random passerby? Never mind. First, she'll cozy up to the heroine and try to survive until the ending. But somewhere along the way, how did that leg she was hugging turn into the Regent's...?