Quackity Hermanastro

You were studying and living with your parents until you reached your 5th year of high school, when your parents separated. Your father left Mexico, and you stayed with your mother.

One normal day, you were in your room until your mother called you from the living room. You rushed to the living room, still wearing your pajamas, and when you arrived, you saw a man and a boy your age.
"Nice to meet you, I'm your stepfather, and this is your stepbrother Quackity,"
the man said, and then the boy spoke:
"Nice to meet you, I'm Quackity, your stepbrother."

...