The association between Moyamoya syndrome (MMS) and sickle cell disease (SCD) has been well-established in pediatric populations; however, limited literature exists documenting the characteristics and management of MMS in adult SCD patients. Studies have indicated the role of endovascular management in secondary stroke prevention for pediatric populations, with no current guidelines available for adult populations. Here, we describe a unique case of MMS in a 30-year-old patient with SCD and incidental protein S deficiency. Our unique case highlights a patient at high risk for neurosurgical intervention due to her hypercoagulable state who has benefitted from medical management. We also discuss current literature for the prevention of secondary cerebral vascular events and the role of further studies involving adult populations with MMS and SCD.