Fastidious
/fæˈstɪd.i.əs/ adjective mediumExtremely attentive to detail and difficult to please; excessively careful and particular.
The fastidious editor rejected the draft three times over a single misplaced comma.
Memory Trick
Say it as 'fast' plus 'tedious' — a fastidious person moves in a painstakingly slow, tedious way because every last detail must be exactly right.