This type of flatmate is the opposite of an early bird. They thrive during the late hours and often work on assignments or indulge in hobbies deep into the night. Initially, this might lead to a mismatch in schedules, but open communication is key to finding common ground. Try to set a designated quiet time so that both of you can coexist harmoniously. Additionally, investing in some earplugs or a sleep mask might be helpful for those moments when you need to catch up on rest during their active hours.