Board Thread:General Discussion/@comment-26391060-20150208102923/@comment-6697950-20150209090733

Kai, ロザリオ seems to come from the Portuguese word rosário. The English equivalent of the word is "rosary". However, Kawahara decided to use the Portuguese version of the word, instead of the actual English one when translating it to English. Since Kawahara's choice is unusual, most people think that the title is meant to be completely English and so they just translate it as such.