In both anime a 'perfect' girl hides her anime-otaku hobby and is discovered by the male protagonist (Nogizaka: classmate, OreImo: Brother) who will support her and start exploring the subculture.
Both feature girls with outwardly perfect lives who hide their otaku hobby from family and friends. Both of them eventually outwardly embrace their hobby.
Both have otaku female leads with male leads that try to protect their secret hobby. In Ore no Imouto, this is carried out by the brother while in Nogizaka, it is carried out by a "guy"
Both are about a girl that is living a secret otaku life
A popular school idol hides her otaku hobbies, which a normal boy finds out. They spend most of the show hiding this secret and doing various otaku activities. Haruka has a romance element that OreImo is lacking, but they're pretty similar shows.
both lead female protagonists are otakus who must keep their obsession a secret from their family
When you cross Seto no Hanayome (minus the mermaids of course) with Ore Imo, you get exactly Nogizaka Haruka no Himitsu.
Both Oreimo and Nogizaka Haruka no Himitsu have the idol-like female who wields good looks, talent, and many fans. However, they have a dirty little otaku secret that is discovered by the male lead. The male lead promises to not only keep their otaku side a secret, but to support them as well. Oreimo lacks the romance aspect Haruka no Himitsu has, however.
-Both involve girls who are popular but are secretly considered otakus.
-Both involve a love relationship, although one is sibling love while the other is more of a romantic "development".
Both series adapts the theme of a young girl who is into anime despite being cute, admirable, and popular at school. She tries to keep it a secret from others besides the main protagonist in the series who knows about her hobby.
Both series' protagonists has a strange relationship but does get along well on occasions.
Both series are lighthearted that has romance, comedy, drama, and similar themes.
They are largely similar in many ways, except Nogizaka Haruka no Himitsu has a romantic theme while Ore no Imouto ga Konna ni Kawaii Wake ga Nai is not (or is it?), not much to say about this one, if you like one you should like the other.
• main character finds out that the heroine is an otaku.
• heroine's favorite animes look similar.(Chibi-like anime.)
• main characters go shopping in Akihabara
Similar situation of the whole otaku business. Both are funny however Nogizaka is more of a rom-com then just a comedy
The main girl is a "closet otaku", she need help of a boy for hidden her secret.
in oreimo, the main girl is "tsundere". In Nogizaka the main girl is "princess-dandere", both have a lots of Fan-service, but Nogizaka is more ecchi than fan-service.
Both female leads are trying to hide the fact that they are otaku's from the others and they end up being discovered by the main guy leads that are voiced by the same actor. Both female leads have more than enough money difference is one tsundere and the other one is shy and kind
These two anime's have a similar concept of the main heroine getting her secret revealed by the main character which is a guy. The main character then helps the main heroine to keep that secret so no one else will know. These two are very much alike but can be different in many ways. If you like Oreimo or even disliked it then this should be the anime for you it has less drama and it has a lot more romance in addition it seems that there are less major problems. Overall Nogizaka Haruka ni Himitsu is the anime for you if you enjoyed Oreimo