A woman on Reddit is furious after her roommate's girlfriend stole her cookie dough.

She explained in a post on the Am I The A--hole forum how the cookie dough theft was her last straw.

"I rent a room to a lad called AJ. He’s 31. He is dating Nina (25f). I don’t mind if AJ has people over or anything but Nina has been here a lot. I am already annoyed because Nina always asks to borrow stuff from me," she began.

"I have always told her no. I don’t make a lot and I don’t loan things. She was furious I wouldn’t give her a pad but I use a diva cup and period underwear and I am NOT sharing those," the woman continued.

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She added that Nina also got mad when the woman wouldn't lend her a dress for a surprise date night.

The woman then set a clear boundary with Nina.

"I told her if she asks again for ANYTHING of mine then she’s not allowed back in the apartment. I told her to stop acting like we are friends and don’t use my stuff," she said.

"This led to AJ being mad at me for making her feel unwelcome. I said I don’t want her around at all and the next time it happens I’m gonna ban her. He said she is not that bad. I ended up letting him know one more step over the line and she’s gone," she explained.

She even told AJ that if Nina breaks the ban he can find a new place to live as he is on a month-to-month lease.

After her warning, Nina behaved herself for a few days before cookie dough-gate.

"I was making cookies from scratch. They come in from some date. She sees the cookies and asks the kind. I tell her chocolate chip and she comes over, sticks her finger in the dough, and takes a chunk," the woman revealed.

"I got so mad I told her to get out. She’s banned. I didn’t care. When AJ tried to argue with me I said I am not renewing his lease if she’s not gone in two minutes. They left and I am now being called an a--hole by friends," she added.

Many commenters agreed with the woman's boundaries and rules.

"If she's been told that you don't like her touching anything of yours, then she should have been able to restrain herself from sticking her fingers in your dough," one person commented.

"You opened up YOUR home and now they're mad that they can't just take whatever they want? F--k that," another person agreed.

"You don’t owe Nina ANYTHING and she’s not entitled to your items or time just bc she’s dating your roommate," someone else added.

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