obsessive
adj.adj. thinking about one thing or person all the time in a way that is not healthy. You use this to describe someone who cannot stop focusing on a specific detail or activity.
adj. characterised by an excessive, often unhealthy preoccupation with a particular person, activity, or idea. Frequently used to describe personality traits or specific behaviours that repeat uncontrollably.
He is obsessive about keeping his desk perfectly clean.
Her obsessive attention to detail made her an excellent editor, though it often caused her to work late into the night.
The detective's obsessive pursuit of the truth eventually alienated his colleagues, who felt he had lost his sense of perspective on the case.
From obsess + -ive.
Often followed by the preposition 'about'. Can be used both attributively before a noun and predicatively after a linking verb like 'be' or 'become'.
He is obsessive with his work.He is obsessive about his work.While 'obsessed' often takes 'with', the adjective 'obsessive' more commonly pairs with the preposition 'about'.