He's not a Vogon, just a very bad poet

The Hitchhiker's Guide to the Galaxy describes Vogon poetry as being “the third worst poetry in the Universe” with Azagoths of Kria coming in second.

The very worst poetry of all in the history of everything is credited to  Paula Nancy Millstone Jennings. Though on the recent tour, the 'editors' of the Guide have been accepting submissions of some rather arm gnawing verse.

But how, I hear you ask, do you write something so mortally bad that the listener's brain actually seeks ways of devolution so that it can return to a primordial ooze with little to no understanding of languages and thus freeing itself of hearing any more?

Well you could use a poetry generator like this:

http://www.bbc.co.uk/cult/hitchhikers/vogonpoetry/lettergen.shtml

Which simulates the twisted dirge of Vogon verse.

Here is my offering from this site:

See, see the Clever sky 

Marvel at its big puke depths.
Tell me, Ashley do you
Wonder why the pug ignores you?
Why its foobly stare
makes you feel tired.
I can tell you, it is
Worried by your humblington facial growth
That looks like
A cheese.
What's more, it knows
Your nudcrumble potting shed
Smells of pea.
Everything under the big Clever sky
Asks why, why do you even bother?
You only charm nappies.

So from this I can deduce, that to write really bad poetry you must:

Use bad imagery

Use very bad metaphors

Use simplistic adjectives

Pay no attention to time or meter.

So, taking this on board, and without computer assistance:

Ode to the furry thing I feed called a cat

Oh thing of fur,

with eyes,

your mouth eats the meat,

in jelly that smells bad.

Like a small vacuum cleaner that likes meat.

You swallow the jellied meat cubes,

That have escaped from their tin prison.

Purr cat Purr.

For that is your way,

Of telling me thanks,

For the smelly food,

Oh purr you furry cat like thing that is a cat.

Job Done