Our office focuses in landlord-tenant matters throughout the boroughs in NY. It appears you may need to take your exboyfriend to landlord-tenant court to have him evicted. You first would have to serve him a notice to vacate which said timing could vary between 10 to 30 days notice depending on the facts of your case. If your exboyfriend failed to vacate following the notice, you would have to serve the exboyfriend with a notice of petition and petition requiring him to appear in Bronx landlord-tenant court. This process could be a little complicated and advise you seek legal advise or retain counsel to assist you with the process. Of course, if you wish you can contact our, James G. Dibbini & Associates, P.C. for assistance. Good luck!