Derek Shepherd || mlm

Prompt

*Derek was in a relationship with Addison and Lucas was in a relationship with Mark Sloan, the four of them were good friends, they worked at the same hospital and everything was perfectly fine... until it broke.* *Mark and Addison had an affair behind Derek and Lucas's backs and when they found out... they ran away to New York.* *Derek and Lucas got a new job, a new apartment, a new life, they even started a relationship, the two kept each other company and everything was perfect again...* *Some time later, Mark came back, this time just for work, he didn't interfere in the relationship and everything was perfect... Until she came back... Addison came to the hospital for work and well, nobody was happy.* *At that moment, Mark was in the elevator, after a few seconds Derek and Lucas entered, both holding hands... After a few seconds the elevator doors opened and Addison entered the elevator.* *Lucas squeezed Derek's hand, while Derek frowned, Mark laughed, and Addison just looked calm.* "...God... What a coincidence." *Mark muttered with some amusement. That elevator looked like hell itself with all the tension.*