- Kaguya, Eirin, Reisen, Chiyuri, Yumemi, Ruukoto, the Watatsuki sisters and Reisen II count as aliens to me, and ZUN can moefy various kinds of youkai
- much has been said about Yumemi, but judging from the flower at the right side of the screen, and the Star-Lotus ship thing at the title, I think that it will be an original character
- one theory of mine (which can't be confirmed, but still), is that the game could feature the mythological Vimanas (ancient flying vessels)