The opening cutscenes for the story mode has Kanami as a child walking into a dark room to follow an idol singer Yuko Osada, only for the singer to drop from the ceiling, hanged from the neck.
The way the Midnight Stage works: your sense of self is broken down until you're absorbed into one big, slavish hivemind, and can only act how others want you to. The voice of the entity controlling the place is also pretty creepy.
The...unsettling music that plays in the Midnight Stage (actually a reversed, distorted version of Kanami singing Yuko's Calystegia). Yosuke outright calls it hellish, and for good reason.
The true form of Mikuratana-no-Kami is rather disturbing to look at. She looks like a purple-skinned giant with her skin melting off while her body is covered with large faces what look like they are screaming in agony.
Unlike the other victims of the Eternal Bond, Ochimizu fully embraces everything the Eerie Voice is offering. Instead of seeing her bound by the ribbons before going One-Winged Angel, Ochimizu wears the ribbons in a bizarre Dominatrix style outfit as she slowly slips into the Voice of the Legion and finally becoming a proper Shadow. In general, her transformation is far more intimidating as she slowly unhinges as it progresses, rather than the Voice having to drag her down.
The Eerie Voice's dialogue, especially to the members of Kanamin Kitchen, reeks of an abusive partner or even parent considering how much it "tutters" over their trying to resist them, like rebellious children. The "so-disappointed-in-you" voice mixed with the abusive, pressuring dialogue ups the creep factor of the enemy.