I like to make things rhyme, I find myself doing it all the time. In any case here are some funny and clever, possibly even cynical, lines I scrounged up that rhyme. The first part is the line that could land you the girl, the second part is the line that could leave you walking away with a handprint on your face.

Roses are red, violets are blue, sugar is sweet, and so are you.
But the roses are wilting, the violets are dead, the sugar bowl's empty and so is your head.

Of loving beauty you float with grace
If only you could hide your face

Kind, intelligent, loving and hot;
This describes everything you are not

I want to feel your sweet embrace
But don't take that paper bag off of your face

I love your smile, your face, and your eyes -
Damn, I'm good at telling lies!

My darling, my lover, my beautiful wife:
Marrying you screwed up my life

I see your face when I am dreaming.
That's why I always wake up screaming

My love, you take my breath away.
What have you stepped in to smell this way

My feelings for you no words can tell,
Except for maybe "go to hell"

What inspired this amorous rhyme?
Two parts vodka, one part lime

Love may be beautiful, love may be bliss
but I only slept with you, cause I was pissed

For me, it was love at first sight
Then the bar turned on the lights

You are the one, there is no other
Oh my god....is that your mother?

I love when you caress, kiss, and hug me.
It's just too bad you're so darn fugly.

I love your teeth, so pearly white
I wish you didn't take them out at night.

Got some good lines to add, I would be more than welcome at the oppurtunity for a good laugh so go ahead. :)