Although funny, this sounds very normal. Our bathroom has two sinks in it and I used to have two adult cats. Guess where I knew I could find them, side by side. They both had their own bed, too but this was cooler for them.
my mom has a persian cat
she says hers sleeps in bath tub
she told me susie likes cuz its cool when my grandma had her
she did same thing at her place
we think its so funny! my husband yells when he sees her LOL