Mochizuki Seitaro was full of enthusiasm as a pyrotechnist, but 1 year later (after the season one finale), his enthusiasm for his work has gone away. He hardly goes out, and he lives like a recluse. His fireworks store, which has been passed down for generations in his family, is still open but in danger of going out of business.
Meanwhile, Mizumori Hikari works part-time as a pyrotechnist at a different fireworks store. In the midst of all this, for the first time in a while – a quarrel breaks out between Wataru and Seitaro. Then, a mysterious woman, Fumiko Noguchi, suddenly visits the shop and not only asks to become Seitaro’s apprentice but also suddenly proposes to him. Seitaro, Hikari, Fumika, and Wataru will live under one roof.
(Source: natalie.mu, AsianWiki)