Hajime Tsunashi is an otaku shut-in that runs a blog, attends anime conventions with his cross-dressing younger brother, and is a surprisingly good cook. Kaoru Tsunashi is a hard-working, smoking, socially-drinking office lady with an overprotective father. Despite coming from two completely different worlds, these two couldn't be more in love with one another… even if she has trouble understanding the vast and complicated world of anime and manga that her husband is deeply entrenched within.

Danna ga Nani wo Itteiru ka Wakaranai Ken is a slice of life anime that explores the life and times of a newly married couple, filled with heartwarming scenes that showcase how the two of them grow as people through their relationships and their friends.