Single coronary artery (SCA) is a rare congenital anomaly in which there is an isolated coronary artery that arises from a single coronary ostium and provides coronary blood supply to the entire myocardium. SCA is classified based on Lipton Classification which includes the origin, branching pattern and course. We aim to present a rare case of congenital anomaly that presented with atypical symptoms and to discuss the features and classification of a single coronary artery. This is a case of a 30-year-old Filipino, male, known type 1 diabetes mellitus came in with diarrhea and vomiting, which later had severe abdominal pain. A consideration of Mesenteric ischemia was entertained due to abdominal pain not compatible with physical exam findings. He then underwent CT angiogram of the abdomen which was unremarkable, so a consideration of atypical presentation of chest pain was considered since patient is diabetic hence he underwent CT coronary angiogram and was noted to have SCA as an incidental finding.