Initially introduced as the attractive school nurse, Mori appears to be air-headed woman who often makes blunt thinly-veiled insults against Teru. However, Kurosaki gradually becomes suspicious of what Mori is capable of when she tries to use Teru to expose DAISY.

Spoiler

In reality, she is actually the true culprit behind various attacks on Teru and Kurosaki, all to obtain information regarding a dangerous project that Kurosaki had been responsible for creating. Because she had been hired by Andou's predecessor as chairman of the school, her background is unknown. When her true identity is exposed, she disappears from the school and remains at large.

(Source: Wikipedia)