Staying vigilant about her surroundings, one dog didn't want to let her guard down when she spotted a set of eyes glaring back through the window.

Owner Charlotte Violet Allen posted a video on her TikTok account @happyenchantedhome of her basset hound intensely looking up at the skylight window, transfixed on the dog that appeared. That, of course, was Moo's reflection, but she didn't put that together. All she was focused on was protecting the house.

Moo didn't dare move as she entered a standoff with her "arch nemesis." Allen's dog has been fighting off the dog in the window since she was a puppy. She stands loud and proud, her head held high and floppy ears pulled back for business.

The caption reads: "Clearly an evil dog from another dimension!"

Allen gets confused because her dog won't growl at anything. She only growls when the evil dog looks back at her through the window. And what gets weirder is that it's only the window. Moo "couldn't care less" about her reflection in mirrors, Allen wrote in a comment.

She also doesn't care about the cat's reflection. It looks like Moo understands it's a reflection of the cat, but decides to leave it alone. She's only focused on the evil doggy staring back at her.

Each of Moo's reactions to the window and mirror reflections is expected because dogs do not have the ability to recognize their own reflection. An article from Wag Walking reported that dogs cannot comprehend that the reflection is them. Instead, a dog will treat the reflection as another dog or ignore it.

Puppies are usually more interested in the reflection than older dogs. They might believe it to be another dog and want to play. A few signs that your dog is observing his or her reflection include staring, barking, head tilting, exposed teeth or play bowing.

Newsweek reached out to @happyenchantedhome via email for additional comment.

The TikTok clip reached over 82,100 views, 11,700 likes and 104 comments as of Tuesday.

"Every time she looks at it, it's staring back at her. It's clearly evil," said a viewer.

Another suggested: "I'm guessing she's okay with the cat's reflection because the cats not staring back."

One person wondered: "What if this entire time she's just been blown away by how gorgeous she is?"

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