Vic is an evil program that was inserted into Mega Man's brain. He owns an evil juice shop in there and is friends with Mega Man, even though he seems to be evil. Currently he is the newest secondary character to be added to the strip's cast.
When Nate and Chadling were stuck in Mega Man's head, they ask about Mega Man becoming evil again. Mega Man claims that he blacked out after spilling a glass of pure, concentrated, unending evil all over himself. He then points them to a juice stand inside his head where he got the drink. The stand is run by Vic.
Mega Man enjoys this little evil entity inside his head and has many fond memories of their adventures together, although most of these are fake memories that Vic inserted into Mega Man. Vic looks identical to Bob, praises Bob, and labels his stand as "Bob's Evil Juice Bar", but warns not to just assume it was Bob who programmed him.
Later on(Or before that point. Gods time travel sucks, huh?) it is revealed that Bob is indeed the one who programmed Vic into Megaman's head on . His purpose in doing so was to screw with the timeline to the point that it would likely destroy everything, though inadvertantly Vic ended up causing the events of Mega Man 6 to come about, attacking the 8 finalists of the Robot Tournament along with the Mega Man Primary program that for some reason doesn't question the fact that Vic is in his head.
During the battles with the various Robot Masters of the game Vic becomes the sole occupant of Mega Man's mind after the original is seemingly destroyed a' la Captain Kirk in Star Trek: Generations. However whether or not this is truely how it happened or just Mega Man and Proto Man reading it in Wikipedia has yet to be revealed, especailly seeing as how it was Vic himself who wrote that particular entry out of boredom.
In The Epilogue, Vic is finally destroyed by a thorough virus scan by Dr. Light.