In part one I explained some of the reasons for why Sekai could have been pregnant, now I will talk about why she wasn’t pregnant starting with the continuation from part one where I wrote about Sekai tricking herself into thinking she was pregnant. It’s very possible that a fake pregnancy occurred where her body goes under the same symptoms of child birth without actually being pregnant. This can either be caused by stress or believing that she was pregnant.
If Makoto and Sekai we’re having unprotected sex then it’s fairly easy to see how she’d worry about getting pregnant therefore causing her to have a fake pregnancy.
As well as this her morning sickness started suspiciously early showing that the pregnancy could have been fake. During the show Sekai shows a strong attachment and possession to Makoto so having a baby could have been in an effort to try and tie Makoto more strongly to her. This could have been because of the competition that she feels from all of the other girls who want Makoto.
What’s more is that Sekai had no proof to back up what she was saying so she may not even have had a pregnancy tester. This could explain lots of things, for example it would demonstrate her reasons for aggression when told to see a doctor besides the fact that she’s worried about child birth. It would make sense that she wouldn’t want to see a doctor as she would be afraid of being told she wasn’t pregnant and having her lie revealed.
Another aspect to this argument is that we’re underappreciating the cleverness of Katsura. We have good reason to believe that she’s very clever and correctly educated. This would mean that she would actually know where to look when searching Sekai’s corpse for the body instead of having a stab in the dark.
This also means that we’re able to rely on Katsura’s sense of judgement of time. It’s hard to accurately judge the time passing in the show so Katsura would probably know better than anyone watching it (besides the writers) the time that has passed since the time when the baby was conceived.
An argument to this is that it’s hard to dispute the time that the baby was growing as nobody (Not even Sekai) knows the date that Makoto’s baby was conceived. The argument to this is her morning sickness which happens early. It would have had to have been one of the first times they did it for the morning sickness to be at least close to accurate so the baby would have been big enough for Katsura to recognise it.
Overall it’s not exactly certain as theirs too many details in the show which make it hard to tell the specific details around her pregnancy. I do believe that she was pregnant however it’s very easy to put arguments out in either direction. This is really a good thing as it’s a piece of art which is open to interpretation so many people can take many different things away from it. I feel like your opinion is more based on your instincts while watching the show. For example when Katsura said that she wasn’t pregnant I was immediately annoyed and disagreed yet I see someone else easily believing her straight away.
I hope that you’ve found these two posts interesting and thought more deeply to the question of Sekai’s pregnancy like I just have.