The most common and most likely answer to this crossword clue is the 10 letter word MALEVOLENT
I've seen this crossword clue in Independent
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More clues leading to the result MALEVOLENT
- Evil, manly and physically aggressive? Not I!
- Man admits love rejection not heartless but evil
- Evil mouse-like chap not heartless
- Nasty digger swallowing beer – very Northern Territory
- Spiteful bloke, not loveless, accepts rejected affection
- Mother fast to catch rodent — nasty!
- Evil parent fast to capture animal
- Bitter man not gutted about romance being rejected
- Bloke furious dropping one’s bitter
- Spiteful man takes beer before vicious elimination of International chief
Buddy explains!

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 MALEVOLENT mean?
MALEVOLENT adjective- Having or displaying ill will; wishing harm on others
- Having an evil or harmful influence