Aside from /b/, /r/ is the least restrictive board on 4chan. As a result, it is largely a cesspool, and it is well known any request not directly related to porn will be ignored completely (except by the occasional troll) and even porn requests are unlikely to get a satisfactory response.
Due to /r/'s general worthlessness, it has become a common practice to instead make requests in other boards. This is often accompanied by an image unrelated to the actual request. The mods have begun to crack down on requests outside of /r/ and to enforce some semblance of rules in /r/, but it has thus far still failed become a worthwhile board. Unfortunately, the stricter enforcement of the rules has put an end to one of the few useful purposes that /r/ has served: fulfilling requests from worksafe boards that have no NSFW equivalent (such as /co/) by posting the porn in /r/. Now any post in /r/ that's not actually a request will be deleted.
The use of /r/ as a substitute for word "requesting" is fairly common. A simple example: /r/ moar loli.
Is it can be x tiem nao plees?
Is it can be x tiem nao plees? is derived from a cat image macro, it has been adopted by /r/etards as a more subtle means of making requests outside of /r/. For example, a request for pictures of Suiseiseki might consist of posting a single pic of her and the text "Is it can be DESU tiem nao plees?" Like all request outside of /r/, these posts are frequently subject to Sage replies.
/r/etard is the name given to people who post requests outside of /r/. Used differently from its origin /b/tard.