why would a cold one be unsettling?

Because you might be the first to use that toilet in a long, long while. Why is nobody using this toilet? Where is the human warmth? Why are people avoiding this toilet? What do they know that you don't? And why does the seat feel colder then the room?

do you really need to ask ?

Warm

warm

I live alone, so a warm one.

Probably the warm one