Most places I have lived have said not to flush animal waste. The litter can still build up in the pipes. Bag would probably fall into the same classification as the "flushable" wipes. There isn't enough agitation action in the plumbing for the wipes to break down, so they end up collecting in a giant ball in the sewers.
I found a dry erase marker on the floor today. I don’t own any dry erase markers, or a whiteboard. Occam’s razor suggests that previous owners knocked it under the fridge or stove years ago, but it just might be something weirder.
Or a visitor had one in their bag/purse and it fell out, out of sight until now? Unless you don't get visitors very often like me, then yeah.
My sister had devon rex that got nicked named "space alien cat" by another sibling as the cat had rally big ears but I think that one has that kitty beat.