"Nnnnngh... Noooooo," she creaks, shrinking in on herself and glancing away again. "Not exactly. See... At the time, we weren't sure if the Nightshade that Lapis saw was an illusion from one of the books, or the real thing. I told Lapis I wanted to inform Lambert and Sans about the incident right away, because it posed an obvious security threat. But..."

She pauses briefly and glances down at her hands, fingers twined together anxiously. "...Lapis was scared. She didn't want to get dragged into any more trouble, especially not after I lectured her about the dangers of what she almost did. She said she didn't mind if I told the other supervisors, but if I did tell them, she wanted to be left out of it."

Steven can probably see where she's going with this.