>>49370721
well as you noticed they're both chimeras, her omake refers to her as a youkai of unknown identity and ZUN's music note for her theme calls her an unknown being and a Mononoke (a concept that got hashed out around the Heian period which is before the modern concept of youkai got properly hashed out), her theme song definitely has bits of Heian Alien in it
I like to imagine they're sisters