Understanding Misa

Misa is what everyone would call a loner nerd. She gets the best grades, she spends most of her time studying, she doesn't have any friends.
That's what we all think of her, but do we actually know Misa? Do we actually know who she is and what she does when she's alone?
At the end of the day we don't know anything from her perspective, but Isaac will find out who Misa actually is. Whether it's good or bad, you'll never know unless you read.