It seems to me like a fairly obvious thing to treat another person's home in the same way you would want yours to be treated, but unfortunately, there are plenty of people out there who don't do that. In fact, there are some out there who act horrendously without even a second thought as to who they may be affecting.
Just be thankful that you never had one of the people from these Reddit stories in your home...
1. Spirits and fish don't mix"Someone at a party dumped a cup of vodka in my fish tank because "your fish look bored! hahaha!" ... I kicked everyone out and had to change out all the water before they died." - Murkey-Purple
2. The final word?"My sister in law got really drunk and s**t on my coffee table during an argument." - hosstradamus
3. Ban him for life!"Roommate's boyfriend comes over drunk. Roommate was not there but he said he wanted to wait for her, and we were too non-confrontational to make him leave. After a while, he goes into the bathroom and we can hear lots of splashing around, but again, too timid to ask wtf is going on in there. He comes out, sits down, and we notice his arms are completely covered in black marker. Then he says "you might want to clean up the bathroom. there is water all over in there." and leaves.
"He had taken a f*cking black sharpie, colored his arms, then tried cleaning it off and when it wouldn't come off he got the marker wet and splashed black sharpie water all over the entire bathroom. There were puddles of purple sharpie water all over the floor. It stained the linoleum and, despite our roommate's attempts to clean it up, we ended up losing security deposit money over it.
"He was no longer allowed over without her there." - HotDishEnthusiast
4. Too much to drink"Wake up in the middle of the night, hobble to what he thought was the bathroom (he was trashed), and then start pissing against the wall/hallway floor.
"I woke up to the sound of a very heavy stream and then my mom shouting, "WHAT THE F**K?!"- DrProfessorElizabutt
5. The worst dog owner"Had a friend comer over for a weekend thing to celebrate my 6th month of sobriety. He brought his girlfriend, who brought her Cocker Spaniel. Who proceeded to s**t on my couch, and not a solid s**t either,. I'm talking that thick, cake batter diarrhea they get from cheap Off Brand dog food.
"She just looked at me, pinching her nose and said snottily 'arent you going to like clean that up'. My friend looked at her she just had a xenomorph Chest Burster live up to its name right there in the room, got up, grabbed some papertowels, and cleaned it while apologizing to me repeatedly.
"He dumped her the next day because the same thing happened at his parents house." - WeirdWolfGuy
6. Kids will be kids?"I used to host extravagant yearly parties at my house as a thank you to everyone who worked for me. Significant others were fine, but I stressed that young kids were not welcome, because it was an adult party and the house/garden just weren’t child-friendly.
"One of the guests who's a mother decided to bring her 4 children anyway, all under the age of 12, and leave them completely unattended. I walked into my master bedroom halfway through to find they had filled a dirt hole in the garden with water from a hose, made goopy mud pies, stomped around in them, come back inside and crawled into my bed under the covers, and ground their shoes intentionally into my pillow and all the bedding. They also took all the clothes out of my closet, put them on, threw them on the floor and stepped on those, and ruined two rugs on the way.
"The mom's response: "Haha! Well, that's just how kids are, you know. You'll understand once you decide to finally grow up and have some." - ReshKayden
7. What in the world..."Cousin's were visiting and one of them used the bathroom. Somehow managed to get some poop on his hand. Wash it off in the sink? No, I'll just wipe in on the window, so someone comes in later and sees a brown smear. Kid was 14." - Lord_Gilgamesh_III
8. Surprise visitor"A co-worker of my husband's just walked in our back door one night and had the gall to call me a b***h when I told him I was going to call the cops if he didn't leave. Apparently, he thought it would be fine to just walk in because "your husband knows I'm coming over; why are you freaking out?" I'd never met this guy, our kid was asleep, and my husband (who wasn't supposed to be home from work for a couple more hours) hadn't texted me that Dude was coming over; of course I'm going to freak out!" - ServantofShemhazai
9. Dog hater"A beast of a relative came over with his new wife, who apparently hated dogs, but didn't warn us or ask us to move ours into another room. Our jolly, obese Bichon Frise was just walking around smelling people's legs, not even jumping up, and he kicked my poor dog with no warning! I still haven't gotten over it, and I still don't like him." - rose-bradwardine
It should go without saying - but you should treat even your closest friend's house with the utmost respect. Saying that, it's going to be pretty hard to find a guest that acts as badly as the people in these stories.