Because You Stayed

Naruto was able to keep Sasuke from leaving Konoha, but now the Uchiha must be watched at all times by his team under the rules of his probation. But once Naruto leaves on his training adventure with Jiraya, Sakura is the only one left who's able to guard.
Sakura makes an impossible promise to the Uchiha, a promise that brings them closer together as teammates and as something more.