Somehow enrol recluse (5)
'recluse' is the definition.
(I've seen this before)
'somehow enrol' is the wordplay.
'somehow' is an anagram indicator.
'enrol' with letters rearranged gives 'LONER'.
(Other definitions for loner that I've seen before include "Unsociable person", "One shunning company", "One preferring own company", "Hermit", "Solitary type".)