Doctor Tsubaki

Doctor Tsubaki (椿医師) is Sasuke Tsubaki's foster father and the man who delivered Haru's twins. He was also the one who caused the car accident which ultimately took Haru's life. He works at the Tsubaki Clinic and adopted Tsubaki primarily at Haru's behest, as she didn't want Akane to take on a responsibility she couldn't handle - namely, raising two babies. On the twins' seventeenth birthday, he tells Tsubaki the entire story and seeks out Bossun to do the same. He is the one who informs each of them that they have a twin.