A friend?

OK, this girl was walking home from her midnight class and heading towards her room, which she was sharing with another friend. As she was walking, she suddenly heard a voice calling her name. She turned around and asked loudly, " who is that?". However, there was nothing and nobody answered, she was getting a bit scared and decided to head home faster.

When she reached her apartment, she saw her friend there. Her friend was studying and then, she turned around and talked with her for a brief moment. Suddenly, her friend asked the girl to dance and dimmed the lights. She was dancing and dancing, but the girl felt something was wrong somewhere. She turned the lights on and to her shock, she saw her friend was floating and dancing. She screamed loudly and tried to escape but, at that moment, her friend, this time, the real one, turned up and she was even more scared. They both soon saw that the ghost which had taken the form of the girl's friend, laughing and floating all over the room. The girl and her real friend ran all the way out, screaming and asking for help.

What happened after that, I have no clue