Hataraku Saibou Black EP7 - Caffeine, Temptation, and Jealousy

An accident occurs where the oxygen delivered by Red Blood Cell (AC1677) to a young Ordinary Cell transforms into reactive oxygen, causing the Ordinary Cell to age. Though it was an accident, he is overcome by guilt for making a cell grow old. Shortly after, an awards ceremony is held for new Red Blood Cells, where AA2153 is chosen for the Rookie of the Year award. Though they started on the job at the same time, AC1677 is pained by a sense of inferiority towards his coworker, but a senior Red Blood Cell approaches him and says that he understands how he must feel. The senior Red Blood Cell says, “I know a place that will make you feel better,” and tries to take AC1677 somewhere.