Mei-Shun’s diary taught her that 寒蝉, meaning cold cicada is read hi-gurashi, her favorite. 蜩 has been only Chinese character she knew for it, let her imagine the reason written in 2 ways. Her childhood heard them start singing from early in the morning, while around sunset when she tried dancing with Mr. Marumorita today. We do not feel chill at all but cooler wind, darling.