The context of the following conversation is Casey was thirsty, so they poured themselves a glass of water and took a sip.:
Casey says I'm gonna pour myself a glass of water..
The friend responds Sure, go ahead. Take as much as you want..
Casey responds Thanks. I'm really thirsty..
The friend responds I bet. You've been doing errands all day..
Casey responds This water is really quenching my thirst..
The friend responds Yeah, I figure that's what water was meant to do..