Yoshikage Tachibana is the father of Tomoe Tachibana. He is rather protective of tradition, but his disapproval of Tomoe's choice to pursue a career in endoscopy resulted in Tomoe having a fight with him and leaving the clan for America.
In Tomoe's storyline, he calls Tomoe back to Japan, partly due to an illness. He soon collapses due to pneumothorax. Due to the fact that Chief Patel couldn't get a needle into his skin, Tomoe ends up doing endoscopic surgery on him to seal the ruptured bulla in his lung. After a successful operation, he grows to accept Tomoe's choice.