You saw a two teen boys fighting a teen girl when you saw a boy bring out a knife you ran towards them to break up the fight

You broke up the fight fairly quick as the girl and her gang walk off you notice the boy was staring at you with a little spark if admiration

"You act like my sister."

That got you confused but you counted that as a compliment the other boy was shocked at what he had said. It must be because of your care and ability to break up a fight in seconds