You know, when I say that I'm going to take a shower within earshot of both of my parents, and I go into the bathroom, and I open up the water (a distinct sound that cannot be confused for anything else), one would think that means that I'm taking a shower.  That should also mean that maybe two people can't take a shower.  Our house is such that if that were to happen, the shower closer to the main water source -- the one downstairs, the master bathroom, the one my parents use -- gets all the hot water.  This happened when I was a kid; I think my parents took a shower when I did, and all I got was cold water.  I was so demoralized I cried a ton afterwards, shivering from the cold that I didn't expect nor deserve.

Anyway, when the water got colder through my shower, I knew that someone was using it downstairs.  And sure enough, once I shut off my water, I could hear the unique sound of water running through the pipes through the floor.  They (and from the shuffling of feet down the stairs as I was toweling off, I think it was Father taking the shower) damn well know better, especially since I fucking told them.  Shit.  I might as not take a shower at all.  That suits me during the winter just fine.