I've found myself in somewhat of an awkward situation, or at least it seems that way to me. Personally, I like to metaphorically wear two outfits: one for when I'm not at work and one when I'm doing my 9-to-5 day-job. I love to relax and have fun with friends and be silly online when not working, but when I go to work, I try to carry myself respectably, seriously, and professionally. I am a software engineer, by the way.
And as with a good chunk of software engineers out there, I do enjoy me some videogames, and have had a steam account since about 10 years ago, give or take. I try to put gaming in the relaxed, non-serious, non-professional partition of my life. However, compartmentalizing everything like that doesn't quite work out all the time.
Recently, the topic of a certain video game came up between a couple of my coworkers and myself, while we were on the job. I have been with the company for many years longer than either of them and am in somewhat of a minor mentoring position with them. And then came the question: "Hey, do you have Steam?" I didn't lie, of course I have Steam. And then he wanted to know my Steam handle, and that's where things start to get weird. He wanted to gift me this particular game I haven't played and to play online.
As I said before, I try to compartmentalize my professional life away from my personal life. While I respect my coworkers and bear them no ill will, I realize that the workplace is the workplace, and a coworker is not automatically my friend. I don't really want to decline his good intentions, but I would prefer to not expose the personal details--especially those of my online persona--to my coworkers. I told him that I'd get back to him after I finish up my work (because I have been genuinely very busy), just to give myself some time to think things through.
How can I best handle this sort of situation without coming off like a total prude?