"Completed" here on mangadex means that the series is finished in the original language, not that it is completely translated. This series has 10 volumes and was published from December 28, 2010 to July 3, 2014.
Such a lovely art style and sweet storyline! I know some parts might seem cliche but the way the author executed her ideas was perfect in my opinion. The feeling of being with your first love and exploring the nuances of a relationship is captured well~ I cannot wait to read the rest of the series!!