Banished forever

This was. Poem a. B. C. D. E. F. 2.
    Indented, and Boffo fell toppleg from his horse. Lancelot jumped down into the mire, but Arthur was too late (already) to od anytho' it was fairly bog.
    Whemp? Crump. Grungy — immensively express.
    "Splat," said Arthur to the crushed Boffo, who lay there oozingly at his feed. The entire infinity of the cosmic universal everything suddenly fell out of the window.
"Whoops,"
    said
        Pangram.

"What an awful nightmare," quoth Arthur, awaking the next morning, "everything was surreal." So saying, he removed the wombat from his head.

"Good evening," interrupted Professor Karswell.

"Good Lord, is it evening already?" replied Arthur.

"No, but I thought it sounded more sinister."

"I'm afraid you're all too late," shouted Wilhelm, breaking the door down, armed with a pointed stick. "In only five minutes you will be banished forever to Upper Sadberge, Clonmult and Goo.