Moaning Myrtle

Myrtle Warren was once a Hogwarts student, but after her untimely death, she stayed back as a spirit to eternally haunt the second-floor girls' bathroom. Myrtle had a hard time at Hogwarts, and was frequently bullied. Prone to wailing morosely, the ghost became known informally as Moaning Myrtle. But Myrtle did have a cheekier side that came out sometimes, especially when she made friends with Harry. Years later, she would meet his son, Albus, and was equally friendly with him.