I would suggest going for this after getting the Serial Killer achievement:
Your karma level carries over from the main game into Survival mode. Using the 'Kill' option is easier in Survival as the bullets reach much farther compared to using the 'Kiss' option. With a high level of negative karma, your 'Kill' weapon will be significantly upgraded, making this much easier.
After a while, there will be a lot of red splats from all your victims which can make make spotting newly spawning enemies a little tricky. Bear this in mind and move to a cleaner area of the screen when necessary. With the upgraded 'Kill' weapon, this should only take 2-3 minutes. The achievement only pops after you die. Good luck.