Absence Makes the Heart Grow Fonder.

Hatori becomes jealous when he discovers Yoshino being tickled by Yanase. Yoshino explains it was only horseplay between friends but makes matters worse when he announces he and Yanase are taking a vacation to a hot spring. At he spring, Yoshino reflects on Hatori's kindnesses to him and wonders why he was opposed to the trip. When Yanase has a cake brought to their table, Yoshino is surprised to find out it's his birthday and now realizes why Hatori didn't want him to leave. As Yanase prepares to tell Yoshino who his secret love is, Hatori calls, ostensibly to talk business but in reality to wish Yoshino a happy birthday. Feeling guilty, Yoshino rushes back to Tokyo to be with Hatori.