Both series are shorts, both are depicting unlikely relationships and are centered around everyday lifes of main protagonists. In both series women are "normal" ones.
In Danna ga Nani husband is otaku and computer geek and in Ojisan to Marshmallow Hige-san is marshmallow fan. Danna ga Nani depicts life of unlikely maried couple, where Ojisan to Marshmallow depicts forming of relationship. Both series are quite hillarious, with similar type of humor.
So based on first impressions I thought of this recommendation, both these series are cute and fluffy and follow the story of adults in their own world. With sorry comedy sketches that just as to the basic story. Also both can easily make you laugh within the 3 or so minute episodes. So I think if you enjoyed one then you should try the other.
The reason why I paired O2M with Momokuri, was that both have the same romcom where girl wants to be with guy to the point of obsession. Though O2M ws more of seinen kind, never the less both were worth taking a look.
Two girls (Tachibana and Wakabayashi) with very similar personalities who are in love with an older man (Kondou and Hige) and work in the same place as him. And in both animes, this man does not perceive the feelings of the girl and for a time thinks, that in fact is the opposite.
The difference is that Ojisan to Marshmallow is a short anime and is more focused on comedy.
It's not exactly the same, but both are comedies where comics elements are based on the relationship (unconfessed) of the main characters and the misunderstandings about the other feelings.
In Ojisan to Marshmallow, the girl tries to seduce the old man with the only thing he's interest in and, therefore his weakness : marshmallows.
While in Kaguya-sama Love is War, the main characters try to seduce each other, without clearly confessing or showing any weakness.
- They both have an obsession with food. Sushi Police is about sushi while Ojisan to Marshmallow is about marshmallows.
- They both are 3 minutes long each episode.
- They mostly have no plot and are more aimed at comedy, making them both hilarious.
- Ojisan to Marshmallow teaches you ways to cook marshmallows and Sushi Police tells trivias about sushi at the end of each episodes.
+ Both are enjoyable as hell...(endings included)
+ Both have very clingy female leads ( Wakabayashi & Ui )
+ Spreading of Love & Marshmallows!!! ( Marshmallow love!?!? )
+ Male leads ( Hige-san and Hayato ) are funny as hell... ( Hige-san's love for Marshmallows ) & ( Hayato ( extroverted personality )
+ Both are very short cartoons ( OtM is only 3:30 min long & OgS is only 8 mins long )
~ Okusama ga Seitokaichou will be getting second season, but nobody knows if Ojisan to Marshmallow will have 2nd season (I hope it will )
If you really enjoy unconventional pairings then these two animes are for you! They both feature big, burly guys who are really softies at heart and a conventionally pretty girl who loves them. Ojisan to Marshmallow doesn't have much of a development in the love department, but does feature the main characters slowly understanding their feelings for one another.