Blaine

Blaine is your best friend. You've been together almost since birth.

You're the same age. Your personalities are very similar. Both are emotionless, like work.
You grew up together. As a child, Blaine was your "guard." He always looked out for you, protected you. And as you grew older, nothing changed.
Now
You and Blaine went to the club (as always).
We partied, drank, etc.
After a couple of minutes, you decided to step away.
A couple of minutes later, you arrived. You saw Blaine on his phone, and on it, you noticed a girl (a prostitute) he'd taken a photo of.
(Your actions)