laid back - Calm, cool, and collected, like you just won the lottery and

Calm, cool, and collected, like you just won the lottery and you don’t even care.

I’m so laid back, I didn’t even flinch when my dog ate my homework.

My dog is laid back, he just stares at me and doesn’t bark.

My friend is laid back, and he doesn’t even get mad when I eat his food.