This story convinced me to buy two of the author's novels, "There Is No Antimemetics Division" and "Ra", both of which I also thoroughly enjoyed, the former a little more.
SCP-3125 does not exist, as it is not an officially recognized SCP number within the SCP Foundation universe. If you're looking for an SCP entry related to the number 3125, you can create one yourself or ask the community to create it for you.