10. Sister Theresa

Complete story — includes the ending

After an incident at home, Amy asks Cory to make an effort to be more polite and considerate. Cory agrees and practices his new, gentlemanly demeanor at school by greeting Mr. Feeny and holding doors open for his classmates. When he accidentally bumps into a cute girl named T.K. and politely helps her pick up her dropped belongings, she interprets his kindness as a sign of unique charm and quickly becomes infatuated with him. At first, Cory is thrilled to be in a romantic relationship, especially when the school bully, Harley Keiner, and his lackeys begin treating him with unusual respect. However, T.K. rapidly becomes incredibly aggressive and intense, filling the Matthews' living room with overwhelming gifts, including wreaths, sirloin steaks, and a life-sized candy clown. Sensing that the relationship is moving too fast, Cory tries to break up with her. T.K. takes the rejection poorly, and Cory is horrified to discover that "T.K." stands for Theresa Keiner—Harley Keiner's younger sister. A furious Harley corners Cory for breaking his sister's heart and forces him to take Theresa on a nice, polite date to the drive-in theater, appointing his sidekick Frankie to act as a chaperone. Theresa, however, has no interest in a polite date. She quickly bribes Frankie with enough snack money to clear out the concession stand, sending him away so she can try to aggressively make out with Cory. Terrified of making out with Harley's sister but equally afraid of rejecting her again, Cory frantically tries to distract Theresa. He manages to diffuse the romantic tension by asking her about her personal life, prompting a vulnerable moment where she opens up about a childhood memory regarding her father. Meanwhile, Eric attempts to navigate his own social circle but finds himself consistently overshadowed by more popular students. Topanga Lawrence does not appear in this episode. Guest stars: Danny McNulty as Harley Keiner, Blake Soper as Joey, Danielle Harris as Theresa "T.K." Keiner, Ethan Suplee as Frankie, Herschel Sparber as Delivery Guy Absent: Danielle Fishel as Topanga Lawrence