I have seen recently robots.txt for my site & one from my blog (Blogger custom domain) is appearing in SERPs (snapshots attached). I have no idea how did this happen. I have never placed the robots.txt link to any forum or other sites. Whereas I often use these free online website analysis tools like websitegrader.com/woorank.com which may checks robots file while analyzing.
I am not sure, but I hope using url removal tool in Google Webmaster Tools won't be a good idea. What I can do to fix this? Do I really need to care about this?