forget the fact that a dog is being humped by a woodland creature why is there a deer in someones living room… rednecks!

“Antler” and “horn” are synonyms. I'm disappointed in the dearth of puns.

Deer lose their antlers every year, so if you're implying that the person who owns this deer also killed a whole bunch of deer, that's not necessarily true. It's very common for people in wooded areas to collect deer antlers when found. http://www.antler-shed.com/ Antlers are also grown as preparation for mating season, so having them in the background is actually very fitting. :P

He may seem angry, but what we don't see here is that the dog totally owed the deer for dinner.