The most common and most likely answer to this crossword clue is the 5 letter word LAMER
I've seen this crossword clue in The Times
L
A
M
E
R
Buddy explains!

The straight part
We know that "More pathetic" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case more pathetic = lamer.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does LAMER mean?
LAMER adjective- Unable to walk properly because of a problem with one's feet or legs.
- Moving with pain or difficulty on account of injury, defect or temporary obstruction of a function.
- (by extension) Hobbling; limping; inefficient; imperfect.
- Unconvincing or unbelievable.
- Failing to be cool, funny, interesting or relevant.
- A person lacking in maturity, social skills, technical competence or intelligence