I swear there was a thread on just the Ichijiku no Hana PV that had people dissect the entire thing to the smallest details. It was a great thread (on Ringo-Jihen) but I can't find it anywhere anymore.
Not even on the wayback machine archives :/
Found these on there however:
https://imgur.com/Wkmnn5m
https://imgur.com/5W9kTBF
https://imgur.com/OchCZxn
https://imgur.com/L1aeUVZ
https://imgur.com/bnaZsLD
https://imgur.com/r9LTGE1
https://imgur.com/YEjgDxH
https://imgur.com/C7rjroc