Crazy male's out to become close buddy (4,4)
I believe the answer is:
soul mate
'close buddy' is the definition.
(a soul mate is a close friend or romantic partner)
'crazy male's out' is the wordplay.
'crazy' indicates an anagram.
'males'+'out'='malesout'
'malesout' with letters rearranged gives 'SOUL MATE'.
'to become' is the link.
(Other definitions for soul mate that I've seen before include "Friend with a deeply personal relationship, like spiritual spouse" , "One ideally suited to another" , "One's ideal partner" , "Person sharing deep affinity" , "perfect partner" .)