"To be read carefully" joke

I am sure you can imagine
It's as simple as can be.
The place is picadilly
The players are he and she.
She whispered "Will it hurt me"
"of course not", answered he,
It's a very simple process.
You can rely on me.
She said I am frightened,
I've not had it done before.
He started to convince her,
It would not hurt at all.
Finally she consented,
and he started on it.
Half an hour later
Neither spoke a word.
It was rather painful.
Tears in her eyes.
It's hurting quite a bit now.
It must be quite a size.
"Now calm yourself my dear" said he.
His face betrayed a grin.
Just open slightly wider
Let me get more in.
It's coming now he told her.
Suddenly he gave a shout.
Thank god,
You pulled it out.
Now if you read it carefully
It's a dentist you will find,
and not what you are thinking.
It's just your dirty mind.