From Netcomics :

Story of a romance between a university student, Hasumi, and a young woman, Miharu—who also happens to be Hasumi's professor. Miharu is engaged, but after hearing rumors about Miharu with Hasumi, Miharu's fiancé begins to suspect foul play and breaks off the relationship, claiming to have met another girl. Newly single and somewhat lost in her own life, Miharu finds comfort in the arms of Hasumi, never truly believing that the whims she follows while on the rebound will have any lasting effects. Through a series of chance encounters, misunderstandings, and realizations, all told with thoroughly convincing and poetic style, the separate lives of student and teacher become intricately intertwined.