Yamaguchi-kun Isn't So Bad Vol. 9 (Kodansha, 2024)

“You don't mind…if we take things further…?” Winter brings the two of them closer… Satsuki can't stop thinking about Yamaguchi-kun during winter break. She is determined to work hard to become her best self while they are apart! She is ecstatic on the first day of the new semester. That's when they find themselves spending the night alone together in Satsuki's room… Wait, how did that happen?!