What will happen when I runaway?

[El Jefe]

There wouldn't be a huge manhunt for you, but police would look in obvious places (would contact your friends, run through your email and facebook messages, get access to your texts, etc.) If nobody knows you had a Skype and you deleted it, there is a chance that wouldn't get checked. However, if there was genuine concern that you were in a dangerous situation, they can recover the deleted files from your hard drive. Once they learn that you had a Skype account, they can have Skype turn over any files they have on you (that might contain records of what calls you made, even if they don't have the audio or video content of those calls).

The answer is, there is no guarantee that they would find out, but no guarantee that they wouldn't find out, either. And if they decided that they really wanted to track you down, they would find out.