It's pretty normal for pet owners to get two or even more rats, and they generally go well together.
Meanwhile, some male pet rats can fight - and it's quite normal for them, because they love for their own rules.
Here are a few reasons for such behavior.
Territorial disputes are essential
Rats can be territorial, which means they want to protect their space.
If you put two male rats in the same cage without introducing them properly, they might fight over who gets to be in charge of that space.
They feel the hierarchy
Rats have a social structure, kind of like a pecking order. Sometimes, they fight to establish who's the boss, especially if they're not used to each other.
It's all about the competition
If there's a female rat nearby that both males like, they might fight to impress her and be the one she chooses.
Sometimes it's just fear or stress
Sometimes, rats fight when they're scared or stressed. It's a way for them to protect themselves.
Conclusion
Your pets will fight - and it's generally quite normal for them.
If you feel like their fights become too violent, you can try giving them separate cages to stop the fighting.
