There’s a fine line between being comfortable in someone’s home and treating it like a free-for-all.

Things got especially messy when one visitor helped himself to a drink of expired milk without looking twice at what he was pouring.

Suddenly the host wonders if he’s at fault for not stopping his friend in the act.

Keep reading for the full story.

AITA My friend drank 9 day old milk out of my fridge, aitah? I wasn’t inside when it happened, I didn’t offer him any milk

My friend came over to hang out. My wife made cookies and went to a friend’s house with our daughters.

But here’s where disaster struck.

After grabbing a cookie, he helps himself to a hearty glass of milk, takes a gulp, eats the cookie, and bam — slams the rest of the milk.

I’m outside at this point, and he comes out asking about the milk.

The milk had been in there for a while, but this host didn’t know anyone would be drinking it.

It’s 9 days old, and he’s pretty upset.

AITA?

The guy can read expiration dates, can’t he?

What did Reddit think?

There’s no question in this commenter’s mind that his friend got himself into this mess.

His friend really should have known that something was amiss.

Some people just completely lack instincts.

This commenter is left with many questions.

If someone truly has this little common sense, then that’s on them.

Checking the expiration date isn’t rocket science.

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