This episode delves more into the after effects of time travel, namely the Butterfly Effect.
Okarin discovers a lot of stuff that has changed since he started sending D-mails into the past, and these small changes have started affecting other parts of reality that weren’t intended to happen.
The Butterfly Effect describes this phenomenon, where certain changes will begin to affect other parts of realities, which are minor for that certain instance; in which after making several changes in the past, the effects pile up with one another and them convert and create the reality into something different from what it is intended to be. Making these certain changes are irreversible, if not hard to change since you might exert a bigger effort into changing it back; however this is without any risk since the resultant was an unintended result; changing it back to the original reality will be difficult because you do not know at what part of time-space changed for the resultant.
The following are the major items in his reality that have been changed (hopefully, I got them all):
1.) Makise being alive (unintended resultant from D-Mail sent to Daru stating a failure of the conference)
2.) Moeka not buying a new Phone (intended result from D-Mail
3.) Moeka being forgotten by members of the Future Gadget labs (unintended result from D-Mail of #2)
4.) Kou changes gender to female (intended result from D-Mail sent to the past, making use of pager system)
5.) Moeka being remembered by the members of Future Gadget Labs (unintended result from #4)
6.) IBN 5100 not recovered from the Shrine, due to being recovered by someone else (unintended result from #4)
7.) Feyris’ father staying at home (intended result from D-mail sent by Feyris [unknown content]
8.) Akihabara not being an anime district (unintended result from D-mail sent by #7)
9.) IBN 5100 not donated to the shrine (unintended result from D-Mail sent by #7)
So far, these are the changes that have happened to reality. What bothers me is that the unintended results tend to be bigger and bigger, and to the extent of changing a whole district’s reality. The change has been for the worse (in which we might recall, Akihabara is the place where many of the anime paraphernalia is being sold).
Also, one of the problems will be for them to be able to keep track of the changes, and to possibly control the outcomes of the changes sent by the D-Mails. What concerns us is that the change-controls cannot be fit in the mere limited number of characters of the mails– there should be additional information to be sent to the target so that the changes can be at least be contained or controlled. But of course, the Butterfly Effect will always find another thing in reality to change despite the changes that have been controlled in the past.
Looks like the future will be grim for Okarin, since this will actually might make him hesitate into sending another D-Mail into the past. I wonder what kind of controls he will be able to implement, if in case he needs to send one.
See you guys in Episode 10!