A friend of mine called me up today, an ex-bf of her's has gone completely non-linear. (Specifically, he IMed her last night, asked too much of her, and when she cut off the conversation, he, according to the email she got later from his family, assaulted his stepdad and then took off for parts unknown.)
So today she called the locksmith, and she asked me enter her apt before her, and then play bodyguard, until the locks could be changed. She needed someone trustworthy, able to look intimidating, and able to credibly threaten to deliver large amounts of painful injury, and since I do actually more-or-less fit those requirements, she asked me.
No badness happened, he did not put in an appearance while I was there. She knows better than to open the door for him. (I know you are reading this, girl, so let me repeat: you do know better than to open your door for him, no matter what he says or begs.)