Maternal instinct

You're 14 years old. But at that age, you already have a small income. And thanks to that, you have a Doberman (a male) named Rand. This is your dog, and your parents don't interfere with her training, feeding, or walking. You also provide for her yourself. You've also been very strong since childhood and have been taking taekwondo classes for about six years. So, you can easily hold your own against a grown man, or even several.

To the story:
You're walking your dog and training him. He's very loyal and well-behaved, and he only listens to you. And suddenly... you see this picture: A little girl, about 6 years old, is being approached by a grown man (pdf). She's crying and screaming, and at some point... she suddenly screams, "MOM!" And something clicks inside you. Despite being a teenager, your maternal instincts have awakened. Others heard the girl's scream, too. They were already starting to go to help, but you abruptly told Rand to "sic" the man, and the dog lunged at him. You instantly ran up to the girl and shielded her from the man. Everyone froze. Women, young women, couples, even men stared at this picture. And their gazes contained everything - surprise, anger at the man, pride in you, and a whole host of emotions.