A Story About Smoking at the Back of the Supermarket is a Manga/Manhwa/Manhua in english language, Comedy series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

Sasaki, an overworked salaryman, goes through an average stressful day just for a single light at the end of the tunnel: Yamada, the always-cheerful clerk at his favorite convenience store. One day, Sasaki takes an extra amount of time at a company meeting, and by the time he gets to the convenience store Yamada has already clocked out. However, as he leaves, he notices a young woman with piercings smoking behind the store?