It’s great that you’re thinking ahead about keeping things professional. Setting clear boundaries is key—try to keep personal conversations and jokes outside of work hours, and focus on work topics when you’re in the office. If you ever feel things are getting too personal during work, gently steer the conversation back to work-related matters. Regular check-ins with yourself about how you feel can also help you spot any issues early. You’re definitely not alone—many people navigate this balance, and open, honest communication with Mike can go a long way in keeping things comfortable for both of you.