Demeanor of Shini and missing of another kid 12

Shini was in her early twenties , however she lacked liveliness .She would enter the class ,grab the book in her hand and start teaching without even much interaction with students.

She was very cold and had still eyes that barely blinked ,she had dark circles and scary red bulging eyes .

Students hated her from first day itself but her degree and grades were undeniably remarkable.

She never scolded any kid but spoke in a monotone.

Another kid in the school went missing .

(who is doing this? is it Shini ? we will see it in the coming chapters)