Boku to Kanojo no Koi Log

sacrifices himself, what is he sacrificing himself to? Bungo and how the hell does he "die/disappear?" does bungo disintegrate people?

Fumiko is Bungo combined with the absorbed Miri from A. Fumiko can only exist if Miri is absorbed into Bungo, so if Miri is saved then Fumiko could no longer exist.

The problem is that Bungo is making B possible, and yet Bungo is the source of Miri's disappearance so Fumiko's creation is where A and B split. As such, there can only be a single possible route to save Miri since saving her would instantly sever the connection between A and B forever.

When A and B separate, won't Fumiko still exist unchanged in A? A will continue on with Fumiko and B will continue on with Miri. A and B are different space-times. Two space-times cannot occupy the same route except at the point of divergence, otherwise they would cancel each other out(or destroy reality).

1) They save Miri. Space-times A and B continue on their respective paths. Space-time A has Fumiko and B has Miri.

2) They save Miri. Space-time B overwrites A. Space-time A and Fumiko become as if they never existed and B moves on with Miri.

3) They cannot save Miri. Many possible reactions exist depending on the events that occur in B. These include but are not limited to: Space-times A and B continue on their respective paths both with Fumiko and without Miri. Space-Time B is deleted forever by Ritsu from A. Space-times A and B cancel each other out. Reality implodes and existence ceases. Etc, etc.

Sequence a Ritsu, made a program "Fumiko" to lead Sequence B Ritsu to Save Miku from not existing, this would lead to a future without "Fumiko" just like Bungo isn't in sequence B, what's more the 'reason' why Miku disappears and probably becomes a program is because of the scenctist in Ritsu descend dad's lab, meaning that Miku is lead to the lab experimented on and probably transported to an alternate universe, sequence A Ritsu is trying to stop the experiment by using Sequence B Ritsu however it appears like Fumiko may either a) be erased or combine with Miku and this could lead to a whole calmuity(as seen by Sequence A Ritsu reaction) am not sure what Fumiko plans to save Miku from being erased from their unverise but I'm sure that it is going to cost a high price.