So, a couple night ago the front portion of my master cylinder went empty and I had almost 0 braking at all... when I looked at it it appeared as if that went to the back, yet I feel like if my rear brakes went out I'd still have some braking. I filled the front portion up and pumped the brakes and it drank the brake fluid, any thoughts?

 

If you filled it and pumped the brakes,with the car off..does the brake pedal get firm after 2 or 3 pumps? If the pedal doesnt get firm at all..you have a leak somewhere and lots of air in the system. Id say start looking for leaks..could be seeping and not really dripping alot of brake fluid but wet around the bleed valve on a caliper. Check your brake lines..the hard lines and rubber lines.Theres only so many things that can go wrong in a brake system you will find the problem with some digging.