Crash Course In Romance 1x4 Revolt of the Arithmetic Sequence Season 1 Season 1 6 Episodes Haeng-seon gets a taste of the vicious politics among the academy's parents. She later goes to great lengths to make things right for Hae-e. 1x1 - You and I, the Intersection of Two Universes 1x2 - Probability of Encountering Your Enemy at Your Worst 1x3 - Number of Outcomes Where Dislike Becomes Like 1x4 - Revolt of the Arithmetic Sequence 1x5 - The Secret Probability Distribution of X and Y 1x6 - There Are No Correct Answers in Life, Only Best Answers