...well, nothing to say. So I'm gonna just post the link so you can read prologue right away.
And make sure to support the author and the publisher.
PS: Nagare's name changed. In volume 4, 5 and 7 it was Nagare, but in volume 8, 9, 10 it was Nagaru. Since it's also Nagaru in volume 11, I'm changing it all to Nagaru.