I only see cats in the correct collection.

Hint 1 of 5:

One of the cats is special.

Hint 2 of 5:

It's made out of wax.

Hint 3 of 5:

And wax does not stand up to heat.

Hint 4 of 5:

There is also a nice heat source in the college.

Hint 5 of 5:

Try going downstairs to the furnace to find it.