Explaining AOT to my grandma

Grandma: Oh so you wrote a story?

Me: Uh yeah, fanfic

Grandma: What's a fanfic?

*Silence*

Me: a fanfiction is a story based on another story someone else wrote...

Grandma: Oh

*Silence*

Grandma: So what's yours about?

Me: Well its set in year 845-

Grandma: Don't set it in the past! There's history and so on

Me: I didn't write it though! Hanjime from Japan did

Grandma: oh

Grandma: So what is it about?

Me: Well, its set in the military and they fight titans that are giants-

Grandma: Why do they fight the giants?

Me: Well the titans are bad

Grandma: Why are they bad?

Me: Because they eat people

Grandma: Wow, violent much

Me: Yeah I know, anyway-

Grandma: Who fights the titans?

Me: People in the military-

Grandma: so they are heroes?

Me: yeah kinda like that and Eren is a shifter-

Grandma: huh?

Me: he can turn into a titan-

Grandma: how?

Me: By biting his thumb, anyway, they don't know how the titans appeared

Grandma: So how do they appear?

Me: I DONT KNOW

Grandma: so what do titans do anyway?

Me: They eat people and they are still trying to find out how they appeared

Grandma: Right. So who fights them again?

Me: Facepalm