This was quite a cute and entertaining story. The only thing, which I didn't quite understand and could have been approached differently, was the whole santa thing. Nonetheless, I guess it wasn't such a bad idea and actually a bit original in order to make sense the whole getting a little sister out of nowhere. The characters where really enjoyable, from which Choko's and Chitose's being my favorites. I really enjoyed the interactions between Choko and her oniichan, and I couldn't stop laughting at Choko's innocence, and Chitose's daydreams. It was quite interesting to see how Haruma, Choko's Oniichan, matured during the series, becominga good big brother. I also enjoyed reading how his love life progressed during the series, how he had a big crush, got heartbroken, and finally realize who he loves dearly besides his little sister.

Overall, a really nice slice of life manga, with plenty of fan service.