Nuriel doesn't know the basics quite as well, although she was listening a bit to previous lessons. She draws what looks like some kind of cavern, with lava and such, without paying much attention to it. She glances down at the drawing and quietly incinerates it.
"Oops. Well, it wasn't that good."
Something that occurred in the past perhaps?
"Let's just say I've heard of...some beings, and am curious of if my assumptions are true."
This may introduce a dynamic condition and backstory to Nuriel, since Ragnarok wrote up the character for Demons Run, if he/she limits the knowledge of her type of entity to a certain period of time, that prevents Nuriel from originating from a point past that timeframe. Furthermore, even if this condition is static, Nuriel is likely an ancient entity due to how ancient Demons Run is.
"This is pathetic. Why can I only do mischief at night?"
You'd best not be blaming anything but yourself...
Nuriel jumped. "N-no, of course not..." She faded out somewhat like she had the previous night, before returning to normal and then letting Angel's form return, sleeping like an angel...
Whoever was speaking in red text is likely part of Nuriel's development condition, this currently unknown third party seems to know Nuriel and vice-versa.
Using a mindlink bracelet to access Nuriels thoughts may work. Alternatively, Selina could pretend to break and use the opportunity to interrogate Nuriel.