Reimian Empire

Okay, here's the plan. We move closer to the room's exit, close the door, and check the ceiling. If everything looks clear, Livia takes a cloth and uses it to pull on the cobweb (Livia is smart and observant; let her identify the cobweb that leads into the hole and is most likely to attract the spider). Formation: Tsukiko and Dillion stand in the front row, followed by Ayano and Livia, with Castor in the back. The formation is oriented towards the hole in the floor.
Also, if possible, Ayano casts a barrier on us (so we can recast it later if the spider doesn't appear). Position the barrier as close as possible to the front row, including the row itself. If that's not possible, then never mind.