[BakaOnna]

I've always been kinda lost of the Rule X, Y and Z thing. Am I correct to asume that...

Spoiler:

Rule X is basically someone will go crazy in each arc. Rule Y is Tomitake and Takano's death, and Rule Z is Rika's getting Watanagashi'd followed by the Great Hinamizawa Dam disaster. So does that mean that once Rule X + Rule Y happen, it will ultimately lead to Rule Z?

In this arc, everyone is busy trying to prevent Rule X from happening. Despite that, it's important to prevent both Rule X and Rule Y from happening in order for Rule Z to not happen. However, Teppei is literally a bad "piece" that can ruin a world even if Rule X never happens. Is that right?