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AIBU?

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My sister, my bed, her ONS

118 replies

Laptopfangirl · 28/09/2026 16:36

I rent a flat in central London. I was away this weekend with work, and my sister asked if she could stay as she wanted to go out with some London friends. Fine. Not the first time.

I got back late last night and basically went straight to bed. This morning I woke up to discover a used condom in my bathroom bin. She brought a man back! She is single, so I can only assume it was a ONS. I have no issue with her having one night stands at all, but for God's sake clean up the mess! The bedsheets haven't been changed, the bin wasn't emptied. There were tissues in there as well which I presumed were just for makeup and regular cleaning but now God knows what else crosses my mind.

And to make it even worse I think (but can't be sure) that the condom was actually mine! Which would have meant them going through my bedside drawer (which also contains cash and God help me my vibrator!!).

I know my sister will consider it harmless but she brought a strange man back to my flat, shagged him, didn't clear up the mess and had me sleep in the same sheets!

Clearly AINBU to be slightly pissed off at this. But what level of anger is reasonable? A text jokingly calling her cheeky, or volcanic fury, or something in between?

OP posts:
Myli1 · 28/09/2026 18:11

Pinkflamingo10 · 28/09/2026 17:52

🤮 ew so you’ve slept on dirty sheets covered in strange man sweat and jizz and pubes 🤮
i would be raging

Nobody has pubes anymore do they? 🤔😀

Thepeopleversuswork · 28/09/2026 18:12

It is cheeky and disrespectful and I would be pissed off… but I don’t see what difference it makes if its a ONS or not?

A woman is just as likely to be raped or assaulted by a boyfriend, partner or even husband.

Her behaviour needs calling out but the status of her relationship with the bloke she shagged is irrelevant.

MrsBatshitRatshit · 28/09/2026 18:13

I wouldn't want anyone in my home that I had not actually met.

Laptopfangirl · 28/09/2026 18:14

Myli1 · 28/09/2026 18:11

Nobody has pubes anymore do they? 🤔😀

This is a second order question, to be fair. 😅

And also, I do. So finding out I am socially unacceptable is not another worry I want to deal with this evening!

OP posts:
Autumnandwintergardening · 28/09/2026 18:14

JengaCupboard · 28/09/2026 16:44

That is a total cheek. Next time she would be staying in the Travelodge.

I would be furious at some random bloke being brought back to my house, let alone what they did there. It's just grim all round. Totally disrespectful of you and your home.

this

DuckbilledSplatterPuff · 28/09/2026 18:14

worrra a liberty!

Blondeshavemorefun · 28/09/2026 18:14

Disgusting behaviour of your sister

bringing back I assume a stranger , having sex in your bed and not changing sheets

I would say all 3 to her

And not to stay again

MrsVBS · 28/09/2026 18:15

I’d be fuming, taking a stranger back to somewhere you live and not cleaning up is disgusting, that would be the last time she’d be staying in my flat.

DuchessOf · 28/09/2026 18:18

Sasha07 · 28/09/2026 18:01

Absolutely gross. I'd find it so disrespectful for her to bring a stranger (possibly) in to my home. Then to have both of their naked bodies and bodily juices on my bed, MY SACRED BED! Ugh. I'd be mad too, OP. And then to go through your drawers (possibly)... I know what I keep in my bedside drawers so like hell would I want to look in anyone else's, especially family members!

Clearly you aren't the type of person to allow family/friends sleep in your "sacred bed". OP is comfortable with her sister sleeping in the bed when she's not there. It's not that deep.

AnonyMumAuDHD · 28/09/2026 18:25

Sorry - I would not be happy with someone else’s ONS being brought into my home. They could be anyone. Only I have the right to take risks with whom I drunkenly bring into my home. Hope there were no valuables lying around or tech/keys that could have been cloned.

But yes, she should have stripped the bed and put it in the wash and cleaned away all bio traces of her encounter. Grim, as well as putting you at risk.

Thepeopleversuswork · 28/09/2026 18:30

AnonyMumAuDHD · 28/09/2026 18:25

Sorry - I would not be happy with someone else’s ONS being brought into my home. They could be anyone. Only I have the right to take risks with whom I drunkenly bring into my home. Hope there were no valuables lying around or tech/keys that could have been cloned.

But yes, she should have stripped the bed and put it in the wash and cleaned away all bio traces of her encounter. Grim, as well as putting you at risk.

But that could apply to someone she had been dating a year, surely?

Just because you have told someone a bloke is your “boyfriend” doesn’t magically mean he won’t rape you or rob your flat.

Horses7 · 28/09/2026 18:44

Yuk - he could have been anyone - stolen your jewellery and anything else …..plus not cleaning up after herself is a total disrespect - I wouldn’t have her stay again. Has she got your keys??

Laptopfangirl · 28/09/2026 18:44

Horses7 · 28/09/2026 18:44

Yuk - he could have been anyone - stolen your jewellery and anything else …..plus not cleaning up after herself is a total disrespect - I wouldn’t have her stay again. Has she got your keys??

She has her own key to my flat.

OP posts:
AnonyMumAuDHD · 28/09/2026 18:44

Thepeopleversuswork · 28/09/2026 18:30

But that could apply to someone she had been dating a year, surely?

Just because you have told someone a bloke is your “boyfriend” doesn’t magically mean he won’t rape you or rob your flat.

But the choice to take that risk [to bring a random man that she does not know from Adam into her own/OP’s home] should only be taken by OP, not her sister.

And yes, a BF of a years’ length may possibly do this … but she would know his name and contact details so the police can contact and arrest them? With a ONS, they have no idea who this person is.

Sasha07 · 28/09/2026 18:50

DuchessOf · 28/09/2026 18:18

Clearly you aren't the type of person to allow family/friends sleep in your "sacred bed". OP is comfortable with her sister sleeping in the bed when she's not there. It's not that deep.

Clearly that's one hell of a random assumption, but I forgive you for that. Also the jokey tone clearly went over your head. You're right, it's just not that deep, why did you think so much in to it? Are you ok? Thanks for your input anyway, even though it was completely irrational and pointless. Hope your evening gets better 🥰

TealHacks · 28/09/2026 19:01

I would ask for the key back and tell her why.

My bed is a private space and if someone I allowed to use it violated that privilege, they would be losing the privilege of accessing the rest of my space.

Your home isn't a hotel or airbnb. What she did was so out of order, illustrates poor judgment and a lack of respect too.

Dearg · 28/09/2026 19:09

If that was me, and my sister had stayed over , shagged a man, and not changed the sheets, I would be telling her straight. Her sex life is her business, but don’t make it mine by leaving the evidence for me to clean up.

But,y sister and I can be straight with each other without it blowing out of proportion.

Tell her she screwed up and future access while you are away will be in the understanding that you come home to a pristine flat with no evidence of what she was doing in it.

Lucyintheskywithnoidea · 28/09/2026 19:14

I would be really cross at her for not cleaning up!
It sounds like you are close but she’s been really disrespectful of your home.

Motnight · 28/09/2026 19:16

mondaytosunday · 28/09/2026 16:42

Do you know for sure it was a one night stand? Either way, the issue is she didn’t clean up and change the sheets. So say something to her about this. Does she change the sheets when she normally stays?

Also if Op is correct went through her bedside table drawers.

Ponderingwindow · 28/09/2026 19:24

Do people really believe the odds of assault are the same between a man they just met and a man they have spent a year getting to know?

Laptopfangirl · 28/09/2026 19:28

Motnight · 28/09/2026 19:16

Also if Op is correct went through her bedside table drawers.

Possibly. The condom was of the same type that I have in my drawer. But who knows if it came from my box?

OP posts:
Pallisers · 28/09/2026 19:29

I'd be really angry at this. Not changing the sheets/cleaning up is disgusting. But I wouldn't be happy with a man I didn't know being in my home either - without even a request for him to stay.

Munchyseeds2 · 28/09/2026 19:34

Next time she asks, I'd say no and tell her why

Horses7 · 28/09/2026 20:07

Laptopfangirl · 28/09/2026 18:44

She has her own key to my flat.

I’d get it back pronto!

Thepeopleversuswork · 28/09/2026 20:27

AnonyMumAuDHD · 28/09/2026 18:44

But the choice to take that risk [to bring a random man that she does not know from Adam into her own/OP’s home] should only be taken by OP, not her sister.

And yes, a BF of a years’ length may possibly do this … but she would know his name and contact details so the police can contact and arrest them? With a ONS, they have no idea who this person is.

Edited

I completely agree that it should be OP's decision not the sister's. I think its shabby behaviour.

I just think getting hung up on the precise status of the relationship between the sister and the bloke misses the point. Any bloke can rape any woman. Knowing his phone number and address wouldn't magically protect a woman from being abused.

Anyway the point is she shouldn't have shagged a bloke in OP's bed and not cleaned up.

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