 If you liked
Boku wa Tomodachi ga Sukunai
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 ...then you might like
Gekkan Shoujo Nozaki-kun
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If you want a nice school comedy, with some flavor of romance, these 2 are very similar in that sense. They differ, though, in that while in Gekkan Shoujo Nozaki-kun the relationships are all 1x1 and develop quite slowly, Haganai configures a Harem in which the girls all fight a cold war to win the main protagonist.