Later he served Prince Mochihito, and in 1180 when the plan to search and kill the Taira clan, which was schemed by the prince together with MINAMOTO no Yorimasa (Rising of Prince Mochihito), was revealed, Nobutsura helped the price escape to Enjo-ji Temple and confronted the pursuing kebiishi (officials with judicial and police powers) alone.
のちに以仁王に仕えたが、治承4年（1180年）に王が源頼政と謀った平氏追討の計画（以仁王の挙兵）が発覚したとき、王を園城寺に逃がし、検非違使の討手に単身で立ち向かう。