I know the topic is marked but it's bigtime spoiler territory. Just in case someone playing this expected to have a clearer picture of when I got here I'm gonna mark this post only entirely. Early December spoilers.
Ok so yeah it's Adachi. Didn't need a second try on that one.
Even though I had him pegged pretty early on, I don't feel like I did that through all that much deduction. It really was that it just never made all that much sense to be anyone else. There weren't enough important characters. I did realize a some of the stuff they point out about him afterward, namely that he could drop off the warning letters without rousing suspicion and instantly "accepting" Namatame as the culprit from the diary pretty quickly. But I was so focused on him that there was basically no way I wouldn't notice.
I also figured he threw Kubo in the TV and I'm kinda baffled why the team never came to that conclusion themselves.
I didn't figure out in advance of interrogating Namatame that Adachi himself threw in the first two victims, but it makes sense. Also makes Namatame less of a moron. I had started to think Adachi was killing people more personally after they had been thrown in but that was way off. Instead Adachi just sort of fell ass backwards into playing puppet master for most of the story and the MO was always accurate.
I am glad that the story actually did something real with the 2 blatantly obvious suspicious people of Kubo and Namatame.
Oh well time to go kick his ass and then probably punch God because Persona.
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"One toot on this whistle will take you to a far away land." -Toad, SMB3