A 21 year old medical student and his batchmate and girlfriend came to psychiatry outpatient for evaluation. The girlfriend of the patient, said that he is very boring and its getting difficult for her to continue in the relationship. She repoed that 'He is way too serious about studies '. He goes to every single clinical posting and also asks the postgraduates to take attendance. After the college, he routinely goes to library, where he stays till late night and has staed reading Harrison's medicine. A couple of days back he got into argument with a pharmacology professor about drug of choice of a paicular disorder and argued with the professor in front of entire batch. The patient on the other hand repoed, I don't understand why is she upset with me. I am doing the right thing and i don't understand why other students, teachers and principal cannot be as dedicated as me. What is the diagnosis?