A British ISIS fighter who fled to Syria in 2014 took to an online post to criticize the manners of his fellow militants, but said the unification of so many cultures would obviously create conflicts, The Independent reported.

"Our Arab brothers, or Syrians to be more precise, lack….basic manners," Omar Hussain, the militant with etiquette, said.

Hussain, 27, a former supermarket security guard who threatened to bomb Britain, reportedly complained about fellow jihadists invading his space, talking too loudly and cutting the line. Don’t even ask him about stealing shoes.

"Sometimes you would enter a building and when leaving, you would see the person with your shoes walking 100 yards ahead of you and it can be quite irritating," he wrote.

One of the more remarkable examples of their incivility, he recalled, was the time he entered a room to serve food to fellow militants. He remembered being swarmed.

"I therefore refused to give anyone food until every single one of them was sitting down in their seats," he said.