Hahaha, with Kase-sans speedy ass there's no way this book had a chance to develop! She caught her in no time! Perhaps there will be a continuance in through the looking glass?
This is absolutely glorious. As for the abrupt ending . . .
I understand the plot reason for it to end there. Yamada can't outrun Kase, and with Yamada as the White Rabbit who has to lead Kase into Wonderland, the rest of the book doesn't happen.