Clue: Paddy finds him unpleasant, always lacking in cheer? (4)
Answer: HOOR
Explanation: Definition: Paddy finds him unpleasant
HOORAY less (lacking) AY (always). "A Scots and Irish form of whore; a difficult or unpleasant thing or person" says Chambers. This doesn't seem to me to imply that the second usage is specifically Scots/Irish.