That's from Katawa Shoujo. It's a very interesting visual novel. The character there's named Hanako, and the music is her theme. In the spoiler is her backstory, and if you plan on going to play, I suggest not reading.
She has scars from a fire that took place at the age of 8. Her mother protected her, and that's the only reason she's alive. She'd been bullied a lot because of those scars and lived in an orphanage without making any friends. This made her very shy and not very trusting.
You let the darkness wash over you,
And let it rob you of glee.
I wonder now, like every time,
Why do you let happiness flee?
Time and time again, you fall into sadness.
Almost seems you're falling deeper than the sea.
Now it's finally time, my friend.
I've decided I'll try to make you see.
Here and now, I've decided to ask,
That you answer my one and only plea.
Come on now, give me your hand.
I'm going to pull you free.
My partner. A wolf and a kitten. An unlikely pair, but a great pair here.
My perfect forever friend. Mess with her, and you mess with me. You won't want to mess with me, no matter how nice I am.
This person is important to me. It seems like no one is nice to her, but I'm the odd one out. We aren't aren't really related, but I'm happy to consider her my sister.
June 23, 1991. You were born to run.
You're the best Gaia Sis ever. I'll always be kind, respectful, and someone you can rely on and trust.
My lil sis on here. Important to me and will always be a part of my Gaia family. Don't mess with her, or you'll find this fist at a place you don't want to.