I'm not sure whether I'll get an answer, but I'll give it a go anyway...
So, in Tatarigoroshi-hen, Keiichi gets confused when he spends the night of Watanagashi killing Teppei Hojo, but gets told by the rest of the club that they all had fun at the festival with him. Teppei also seems to still be alive and abusing Satoko after Keiichi "killed" him.
WTF?
I've just finished playing all of the answer arcs and I can't seem to find anything explaining what happened. Did I miss some vital information somewhere, or did Ryukishi07 forget about all of this and not bother to explain what happened in Minagoroshi-hen? Did Keiichi just go crazy and imagine everything because of the virus?

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