Why do some fictional characters feel more real than actual people?

I was thinking about how certain movie characters end up feeling so familiar and human, even though we only spend a couple of hours with them. Sometimes I feel like I understand a characters motivations and emotions better than people i’ve known for years.
I think movies let us see their inner world in a way real life doesn’t.

Does anyone else get weirdly attached to a character because of how real they feel?