Bong.

Seil can imagine the sound that a bell makes if it were made out of a beef wellington.

Because it's late and I can't sleep, for our next question:

Can you imagine a universe where time moves backwards and effect precedes cause, and Seil lives there maybe? What is he doing there? How does he smell?

A bell made out of beef wellington wouldn't ring. Beef wellington doesn't have the right acoustical properties.