It was a normal day aboard the TARDIS, The Doctor happily traveling across the vortex when his phone rang. "Hello?" he answered excitedly. "Is this The Doctor?"
"Yes."
"Yes! We've been working on communication between parallel worlds! How is it over there?"
"It's great. Hey, can I speak to a, um, Rose Tyler?"

Silence

"I'm sorry, she died a week ago in an accident. But she wanted you to know she loved you immensely."

The Doctor hung up slowly. He felt his eyes moisten and after awhile, his cheeks got wet. I never got to tell her. She died before I could hear her voice again. It's my fault she was stuck there in the first place. I-I hate this feeling. I feel useless. I feel like I want to go and be with her... Why did it have to be her? It should have been me because I hate this. The feeling she's dead and I'll never see or hear her in person. I-I never got to say goodbye properly... I-I'll never forget her, or what she did. Not one day or one line. I swear. But before he left the console room to mourn, he did one last thing: he called her phone, just to listen to the answering machine.

Hello, this is Rose Tyler! Unless you're The Doctor, call back another time! If you're The Doctor, come here. Please.

He heard the beep and clutched the phone to his chest.