On Valentine’s Day, Kashiwada gives Oota chocolate. Even though her face stays completely expressionless, the gesture clearly feels special. Oota, of course, becomes extremely flustered and embarrassed, since getting chocolate from Kashiwada makes him overthink everything.
Then the episode continues with White Day, when Oota wants to return the favor. He spends a lot of time worrying about what gift he should give back, turning a simple situation into a huge emotional dilemma.