The Fat Friar glides into the room where the first-years are waiting, alongside almost twenty other ghosts. He is heard telling one of the other ghosts that they should forgive the poltergeist Peeves, and give him a second chance. He smiles around at the first-years, and tells them that he hopes to see some of them in Hufflepuff, his old house.
The Fat Friar is the Hufflepuff house ghost. At Nearly Headless Nick's Deathday Party Harry, Ron and Hermione see him chatting to the ghost of a knight with an arrow sticking out of his forehead.
The Hogwarts ghosts held a council meeting to decide whether to allow Peeves to attend the start-of-term feast. The Fat Friar was ready to give the poltergeist a chance and allow him to go but was ultimately overruled.