Hello there, I'm sorry to hear about this!
Can you ask for a replacement for free? I think this would be the best solution.
There is something called color calibration here in xda, you can search for it.
The problem is that some devices don't have lots of people working on it (Nexus 5 owners had a lot due to a bad calibration and a yellowish screen) but if you can't replace it I'm pretty sure you can calibrate it.
Have a look here: http://forum.xda-developers.com/show....php?t=2754491
but if its possible I would ask for a new LG G2 first!
Don't forget to thank me if I've helped you!