She sees Bellatrix for the first time in the Department of Mysteries, really sees her. She catches her breath, her stomach feels funny, and she thinks her heart might have stopped beating. How can she be so beautiful? She's evil, sadistic, a death eater, a murderer, she is against everything Hermione stands for. But, she can't take her eyes off of her. Her dark, wild hair, her perfect red lips, her sunken cheeks, her voice. God, her voice.
Someone is speaking.. is it Neville? Harry? She doesn't care. She's never seen anyone this beautiful in her life. Surely everyone is wrong, she can't be evil, she can't be a murderer. There must be some mistake, someone must be lying. Because Bellatrix looks at her, and Hermione thinks she could spend her life staring into those eyes. She could spend her life with Bellatrix. She could love her, she could take care of her, give here everything she wants, she could make her happy.
How long has she wanted to feel like this about someone? She's tried so hard to feel this way about Ron, but she doesn't. She can't. Somehow she thought love must not be for her, that she would never fall in love. But Bellatrix.. just one look, just being 5 feet away from her makes her feel everything she ever wanted to feel. Love can be for her, she thinks, she could live for Bellatrix. She would leave all these silly teenagers, she would switch sides if she could feel this way forever. Involuntarily, she takes a step forward. She doesn't even realize it until Harry grabs her arm and yells "NOW, stupefy! Run, Hermione." "No," she thinks, she might even say it out loud because Bellatrix looks at her again. Bellatrix smirks, then cackles. "Filthy Mudblood, you disgust me. You shouldn't be allowed to even think about me. I would never dirty myself with you."
Maybe love isn't for her after all.