A guess I have after finishing chapter 1 .

I have a sneaking suspension that cloning is going to be a major plot twist in this . The evidence:

- the duality themes like twins. The dna logo , the two mascots

- kaguya's character feels heavily inspired by rei from eva

- moichi's arms being healed and the fungus stuff in the flashback . ( This could actually explain how he is alive at the start of the prologue flash forward)

- hints that reiji might somehow be alive because of the end credits scene even though the body itself is clearly dead .