Borris is the name given to each subsequent in a series of snow golems that were owned by Firefoxx. As is to be expected, these snow golems were frequently killed, hidden or set free by the other players on Mianite. The most recent Borris was spawned underground in a specially designed room for the Snowman that was build by her boyfriend, Jericho.
Another time that a "Borris" died was when Jericho build a saw challenge for his girlfriend and build a Borris Imposter for Sonja to kill against her own will.
In Season Two the same sort of stuff happened, though a bit toned down. The first Boris was spawned in a cage behind Sonja's Such Cute OMG house by someone, shortly after The Great Anvil Storm of 2015. A second Boris was spawned under Sonja's basement in a little see-through habitat, though it was very small and housed many pets throughout the season.
In the Season Two Finale, each main player that was there that day, Sonja, Tucker, Sparklez and Wag, were faced to kill something the loved. For Sonja it was Boris, for Tucker it was Sonja, For Jordan it was Jerry and for Wag, it was Kevin. Sonja had to kill Boris and throughout the challenge he died in front of her multiple times.