Summer vacation means hours at the arcade! Umaru instructs in the fine art of enjoying summer like a (lazy) pro. Later, Taihei endures another typical day at work.

In the Doma household, winter means lazy days beneath the kotatsu! Umaru reflects on her interesting year while Taihei tries to collect on a promise she made to him.

Umaru gets sick, but it’s a good thing her germs are as lazy as she is! Sadly, her germs show her brother no mercy. Later, Taihei remembers a day at the arcade, 10 years ago.

Taihei leaves for a business trip with his co-workers. While his boss Kanau thinks of a way to spend time with him, Taihei has his hands full with a vacation-happy stowaway.

Umaru and the girls head out to spend a fun day at the amusement park, but Kirie is having a few struggles. Will the day end up a total disaster?

Sylphin invites UMR over to her house, where a slight misunderstanding leads to some awkwardness. Later on, Umaru seems to have found a weakness in Hikari’s armor.

Kirie devises a new plan to bring Ebina and Taihei closer. However, Taihei might have a couple to many little sisters fighting for his attention already.

It's the end of the year, and everyone is figuring out what Christmas gifts to get their loved ones. Can Umaru and the others find the perfect presents?