As summer vacation begins, Renge’s older sister Hikage comes home from her school in Tokyo, hoping to impress the others with her know-how about city life only for Hotaru to outshine her. Later, Renge meets another girl her age named Honoka Ishikawa, who she quickly become friends with. After spending several days playing with Honoka, Renge is saddened when she learns Honoka had to suddenly leave due to her father’s work. However, she cheers up a week later after receiving a letter from Honoka saying she’ll come back next summer.

After sleeping through the New Year, Renge joins Kazuha, Hikage and Kaede as they decide to go up a mountain to watch the first sunrise of the year. Along the way, Kaede recalls five years ago when she was first asked to look after the one-year-old Renge, initially finding her to be quite a handful but soon taking a liking to her. They eventually manage to reach the top of the mountain and watch the sun as it rises.