She passes by Ami again on her way to the tables, who's leaning back in her chair at a computer with her eyes closed, rubbing her temples. (An unusual number of people are at the computers, most of them staring blankly ahead.)

Luna slows as they pass Ami, sniffing the air.

That is a little weird.

"Do you sense something?" she whispers once they get to the table.

"Energy – a lot of it. It feels odd, though, differently so from you or Chiba-san, and it... I shouldn't be sble to sense it this easily."

"There's a lot of strange energy here in general, too. More than yesterday. Something's wrong." (If Erika focuses – really pays attention – she can feel it, too, though even just paying attention to the aura of stress and anxiety makes those feelings want to creep into her own mind.) 

"...The library doesn't usually feel like this. Can we do anything?"

"It's possible there's a curse, or enemy activity... We can track down the source. Speaking to anyone affected might give us a clue, but also risks revealing our positions."

"I don't see how else I could help, unless there's some kind of magical sense I haven't unlocked yet."

"You should be able to sense the same things I can, though you need to practice... And it'll be easier as Sailor Moon."

"We could also follow someone subtly."

"I don't want to transform here... Let's keep an eye out and see if anyone leaves suspiciously."

"Alright."

No one leaves suspiciously, at least not right away – in fact, suspiciously no one leaves. Usually, people would slowly peel off over the afternoon, or at least drift to other parts of the library. The students at the computers seem pretty glued to them, except Ami who's only a little stuck, and who continues her odd cycle of staring at the computer and then either shaking her head or rubbing her temples. 

Okay, that is kind of weird. She could sit here and just wait but that doesn't actually seem very 'Guardian of Justice'-y. That's the sort of person who would take a proactive approach. Maybe that can be her now.

Erika doesn't know most of them but she has at least half an excuse to speak to Mizuno. She will walk up and clear her throat a little awkwardly.

"Hey."

She blinks and jerks her gaze away from the computer, looking at Erika with an almost startled expression. "Tsukino-san?" she asks, bewildered. 

"Mizuno-san. What are you working on?"

"I'm studying – my cram school insisted we use this program," something twitches in her face, and she starts to look back towards the screen before shaking her head and looking back at Erika. "It gives me a headache, is all..."

"Cram school already?"

"I need to be the best..." Her gaze starts drifting towards the screen again. (And, even as socially isolated as Erika is, Erika's heard the rumors – the idea that Ami's IQ is over 300 is probably silly, but every time rankings are posted, Ami has perfect marks, scoring at the top of not just her school but of their grade across all of Japan.)

(She no slouch herself academically, but she will freely admit she has no desire to put in the work to reach those kind of heights.)

"I've heard it's not good to spend too much time looking at a computer screen. Maybe you need a short break, if you're getting headaches?"

Her gaze snaps away from the screen again. "I've always preferred books," she admits, "I think computer programs honestly put too much distance between you and the material..." She pushes back from the computer, reaches out towards the tower, "But the cram school's been insisting on this new pro...gram..." 

Her gaze goes blank, and she turns back to the screen.

Luna makes unhappy cat noises from Erika's feet.

"Mizuno-san?!"

No response!

Mrrr...

Luna lashes out at Ami's bare ankle, claws bared.

" – Uwah!" She jumps up from her chair, away from the screen. Her eyes are back to normal.