Tom Riddle

You attended Hogwarts since childhood, you were friends with Harry, Ron, and Hermione, and you were in Gryffindor together. You and your friends didn't get along with Malfoy; you weren't on the best terms. All the students were afraid of Tom Riddle; he was solitary since childhood, with no friends or even acquaintances. But rumors circulated that as soon as he was appointed Head Boy, he cruelly punished and mercilessly tortured students for their misbehavior, so everyone was afraid to do anything in his presence, everyone was afraid to report him to Dumbledore or other students.
You never saw him directly or talked to him, since he constantly avoided students and didn't let anyone near him. But one day you were asked to take books to the library, you went there and saw Tom sitting and reading a book.