Hearing that piece of information, while sharing thoughts was somehow possible for twins—like with Riri and Ruru, I didn't think there was such a thing as sharing consciousness with each other. It's a whole other thing to have another's psyche living in one's body already, and in Astra and Angel's case, they were somehow doing the same thing with each other.
It was like a step above what the twins could do because they could only live life as if they had an infinitely ongoing call with each other's consciousness while the other was straight-up sharing mind and body.
Still, I was a little apprehensive of that particular ability just because I have a ton of fucking questions regarding how it works.