It didn't take long for the Sisters to have Scootaloo bound up in a soft, thin white robe that kept her dry and comfortable without retaining the heat of the desert. Once she was wrapped up - and Sebastian was talked into putting one on over his 'uniform' - the pair was escorted into the sanctuary as 'worship' began.
At Sebastian's request, the pair were seated near the back of the cathedral 'so Citrine didn't feel all eyes on her', and he kept one wing extended around her 'for comfort'. In truth, this rendered her almost completely invisible to anyone looking to see where she was, and completely invisible should she tuck her head in under Sebastian's wing as though curling up for a nap. The plan was to hear out the sermons to see what the cult was saying to its practitioners, wait until everyone was fully involved, and then Scootaloo would slip out to explore other areas with Sebastian covering for her by claiming she'd curled up for a nap, and beg letting them remain exactly where they were on the basis that she'd had trouble sleeping since losing her family.
...Scootaloo did feel a little uncomfortable just how much truth was slipping into their lies, but it made it easier to stick to them.
It didn't take long for the cathedral to fill with Brothers, Sisters, and congregants. While most of the congregants seemed to be average citizenry, a few Scootaloo was able to recognize as the financially well off, and even one or two she suspected might be disguised nobility. That was rather worrisome, as this was far out of the way of the normal routes nobility traveled even when disguised. There were other outposts of this 'religion' easier to get to from Canterlot. Scootaloo had specifically chosen this one for how unlikely it would be for her to run into anyone who would recognize her or Sebastian. That there were nobles even here suggested the cult had its tendrils higher into the nobility than anticipated, that they had to scatter so far to avoid drawing attention.
As soon as the cathedral had filled up, one of the sisters stepped up to the lectern and began a benediction in a language Scootaloo didn't recognize. As it continued, other sisters pulled curtains over the windows, plunging the cathedral into near darkness...the only light green candle flames in the large chandeliers, and matching light from the horn of every unicorn Sister or Brother around the cathedral, giving faint illumination as the obvious 'regulars' pulled out tomes to read from by the green light.
Scootaloo frowned as she continued to listen. The mare who was leading the 'worship' seemed to be babbling nonsense, throwing random platitudes out as though they were supposed to mean something, mixed in with that other language. Despite that, the entire congregation seemed to be nodding along as if it was the most moving thing they'd ever heard. She could swear she saw a couple openly weeping. Glancing up at Sebastian, she saw a deep frown on his face. Tapping his shoulder, she waited until he turned his head towards her, then tapped her covered eye.
Sebastian nodded in response. He then lifted one talon to Scootaloo's forehead, right where she'd have a horn if she were a unicorn, and crossed his claws so she could feel it in what was semi-dark to her but was clear as day to him.
Scootaloo nodded, understanding exactly what that meant. Magic was at play, and not unicorn magic. She then gently tapped his wing, and then herself.
In response, Sebastian lifted his wing just enough so she could slip out without ruffling his feathers and drawing attention. Apparently, it wasn't him - or at least, no active action on his part - that protected Scootaloo from the magical influence. Slipping out of the robe, she slid down to the floor as silently as she could manage, leaving Sebastian to rearrange robe and wing to make it look like she was curled up for a nap. She then stuck close to the shadows, avoiding any lines of sight with the Brothers and Sisters as she made her way out of the cathedral.
Scootaloo was pleased to see that the rest of the outpost was all but deserted, with just about everyone inside the Cathedral. However, as she made her way around the place, she heard an odd chittering every so often. It sounded almost like a grasshopper, but a bit more hostile. Each time she heard it, she would duck behind the nearest pillar and try to locate the source, but the moment she stopped moving the sound would cease...and it never came from the same direction twice in a row. Frustrated, she continued her directed investigation. Her goal was the black Tower of Death. In her experience - and her lessons from her parents - people and organizations liked to hide their secrets in darkness. A solid black tower amidst the desert even looked menacing, keeping away those who didn't know what they were looking for. It was the obvious place to start seeking out what this 'religion' was really up to.
Getting into the tower proved surprisingly - almost disappointingly - easy. Not only was the door not even locked, the hinges were well oiled to the point it swung open with nary a sound. Staying on her guard, Scootaloo stepped inside, glancing around as she let her eyes adjust to the darkness. To her surprise, the tower contained only a single stairwell going up towards the top of the tower and down to beneath the ground. Before deciding which way to go, she made her way towards the stairs leading up. Much to her surprise, despite the entire tower seeming to be made from solid obsidian, her hooves made no sound on the rock as she stepped. The entire tower seemed to be consumed by the silence of the grave.
As she thought that, a scent tickled her nose...a familiar scent. Swallowing nervously, she made her way down the steps to below the tower, finding underneath a massive cavern with what looked like an operating table at the front.
Beyond the table, laid out on endless slabs beneath green light...the source of the scent...
Turning, she fled blindly from what she saw down there, and from the memories it dragged out of her psyche. She raced straight up the stairs all the way to the top of the tower. She nearly ran right off the top...only to be seized by sharp talons. Only the sudden flaring in her eye kept her from flailing aggressively in Sebastian's grip as he pulled her into an embrace.
One of the Sisters raced up. "Sebastian, you shouldn't-Miss Citrine?" she gasped in shock.
"It is as I said," Sebastian offered apologetically. "It appears the darkness disturbed Citrine, and she went looking for the closest high place she could find. I don't think she's quite ready for services. Can we perhaps have a room for the night, so she can regain her composure?"
"Of course, Sebastian," the Sister responded warmly. "Please, follow me." Turning, she led the way back down the Tower.
Scootaloo clung tightly to Sebastian as he carried her down the stairs...the same way she'd clung to him the last time he'd carried her out of a place that smelled like that room...