We've been tracking Shikimori's Not Just a Cutie as anime of mystery.
The first trailer hinted and the second confirms. There's a dark side to Shikimori, and it's kinda cool.
Shikimori and Izumi are high school sweethearts. They hold hands walking home from school, they flirt in the halls, they tease each other. But Shikimori knows what she wants, and how to get it, and she can turn from cutie to cool in an instant.