In defense to Chuuya, if I broke into a prison to find MY boyfriend dancing with another man I'd shoot them as well. You wouldn't? Good for you. I support gay rights, gay wrongs and gay vengeance. We're not the same.
Alternatively, if I was Dazai, and my boyfriend was helping out my arch nemesis, I would drown them. What? You're possessed? Yeah right, likely story. Into the juice with you.