the chamber of darkness (second book to the series)

It's Ren's second year at Hogwarts school of witchcraft and wizardry and she can't wait to see most of her friends again. But when Ren goes forth for her second year she meets a flashy new defense against the dark arts teacher and the boy she's been crushing on sense her last year of Hogwarts becomes her boyfriend things go for the best. Or so she thinks. But her life takes a sharp turn for the worst when kids are found in comas and it's said that there is a monster hiding in a chamber under the school that was put there by Salazar slytherin. But this isn't his first chamber and this one holds a much different thing than a giant serpent.