To my vague understanding, first chapter is about Iku and Tenshi's meeting and how they set to the journey of Bhavagra and retrieve the sword. Then, in one page, Iku and Tenshi was falling. More of explaining why, when, and where they are. It proceeds until they got separated.
Second chapter was all about how Iku and Tenshi fared in their separation. Third chapter was about the meeting and something.
My explanation, I highly doubt, but that is all I can make out.