Bart becomes Nelson's best-friend when Marge forces him to attend Nelson's b-day party that Bart has convinced everyone else to skip. Under the protection of Nelson, no one can mess with Bart, however, Bart can't hang out with Milhouse anymore. Meanwhile, Lisa and Homer bond over a fantasy book that he reads her each night before bed. Homer gets sucked into the book and reads ahead, when he discovers that the book ends with sad news, he creates a story to tell Lisa to protect her from the truth.