Vampires perhaps circling house in ludicrous descent (6)
I believe the answer is:
bathos
'ludicrous descent' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
'vampires perhaps circling house' is the wordplay.
I cannot really see how this works, but
'house' could be 'ho' (abbreviation for house) and 'ho' is found in the answer.
'vampires' could be 'bats' (I've seen this in another clue) and 'bats' is present in the remaining letters.
No letters remain.
This explanation may well be incorrect...
'in' is the link.
Can you help me to learn more?
(Other definitions for bathos that I've seen before include "Ludicrous descent from serious to trivial" , "Anticlimax, descent to something trivial" , "Unintentional lowering of tone" , "Ludicrous descent of mood in writing" , "Serious-to-trivial switch" .)