Futakoi

I thought it had the same touchy feeling at a few parts, but maybe not as good of a storyline, but i loved the storyline still. jsut that i wish it were longer, lol, but that goes for any anime that ppl like. 

Harem comedies that rely a lot on coincidences, where every love interest has something oddly specific in common. In Futakoi, pretty much every single female character has a twin sister. In Nisekoi, every female lead hold a key that is connected to the past of the main character, and most of them have something to do with the yakuza. The names are also similar, both being a play on the word love and the main theme of the show. 

both about a guy who meets 12 Girls. the girls start too like him ,and so on the Differences between Sister Princess and Futakoi Sister princess dosen't have twins and Futakoi is about Twins. But they Both Have very heartwarming characters  

Same music sang by the band Eufonius for both Animes. And its also a Harem anime. 

Both are calm-paced harem shows, and in addition To Heart 2 has a pair of twins in the harem while Futakoi IS about twins. 

twins twins twins