The fuck? Why did the mug disappear at the end? As far as I know, it has nothing to do with the 2 girl's paradox dilemma.
Did I miss something?
BUT why would she disappear? so he's forced to choose one an the other disappeared? Still that's something to consider
the rest standard romcom fare, waiting to see when realizing the big implication of the multiverse
I think this manga is using an idea from a sci-fi show I’ve watched before and altered how it works.
From Stargate SG-1, There’s a concept called entropic cascade failure. This happens when multiple versions of the same person are existing in the same reality. Eventually as time progresses, the non-native ones will suffer issues and eventually die as the host reality is actively rejecting them. This does not happen if said person was already dead and another version from another reality showed up. In this case it seems MC has to choose for some reason.
Now from how I’m seeing it. Author is using this, altered how it is employed and expanded it to also affect items relating to the Sui that doesn’t belong to this reality. Anything that she’s bought that will directly be linked as hers, will be forcibly deleted from the reality. Since reality itself is rejecting her existence.
Reality itself has basically only given him two options. Sui from the alternate reality disappears, not sure if this means she’s erased or ejected back to the alternate reality. Or, reality corrects the issue and kills off the Sui that belongs to this reality in order to allow the other Sui to exist. And if we’re following the earlier concept, it’s trying to erase the alternate Sui first.
Basically they both can’t exist in the same reality at the same time.