How would it look like from reviewers' point of view if one submits off-topic works for application to phd programs? By a scientific work I mean any work of mine that either belongs to my field or belongs to some related fields of my field. A work that is not a scientific work is called off-topic.

Since I occasionally (but seriously) compose poems and popular songs, I am wondering whether it is suitable to integrate these off-topic works into the collection of my scientific works that is prepared for application to phd programs. 

My principal concern is that I am unsure about how this act would look like from the reviewers' angle? Would it be deemed an affectation? Indeed, my wish is merely to present more of me.

Hope ladies and gentlemen (preferably with experience as a reviewer for phd admission) would share me your thoughts, much appreciated.  

If answering this question requires more information, please feel free to state that.
Being a mathematician, I must address a logical loophole: I will assume that your field is a STEM field and thus poetry and songs are actually off-topic (and not just called off-topic).


  How many legs does a dog have if you call the tail a leg? Four. Calling a tail a leg doesn't make it a leg.
  -- Abraham Lincoln


Assuming this: no, I would not submit such creative materials as part of an application to a STEM PhD program.  I wouldn't go so far as to say that submitting such things would be deemed an "affectation": however, unless you make a clear connection to your chosen field, they are simply not relevant.  Including irrelevant things is not a disaster, but it does indicate that you don't have a clear understanding of what is relevant information in the consideration of your own prospects in that program, which is not great.

Most such applications have a personal statement.  Mentioning somewhere in the personal statement that you write poetry and songs sounds about right to me: from one human being to another, that is interesting, and personal statements are often not so interesting.  But be careful here: a "personal statement" is not a statement about you as a person!  It is really an essay explaining why you would be a strong candidate for the program, so things which are not relevant to that should not be dwelled upon.  

Many programs do look at the personal statement as a writing sample -- and good writing skills are very relevant in any PhD program, probably more so than any other single quality -- so if you are an unusually good writer the personal statement would be a good opportunity to show your superior skills.  However, trying to do that in the genre of either poetry or song would be so risky and open to negative reactions based on personal taste that I wouldn't recommend it: after all, in most STEM programs you need to be able to write prose, not poetry, and you are not really permitted to burst into song.  This is probably a "color between the lines" situation.

Added: I spent four (recent) years on the committee in charge of graduate admissions in the UGA mathematics department, and I still read some PhD applications every year.