He is a cold-blooded assassin.

Lewd words and delicate scholar bottom & Reserved and silent, but still waters run deep, fox top

Alex always imagined meeting his mate and falling for him hard and fast. He imagined his mate being nice and gentle. But when he finally met his mate he relised that none of those wishes were coming true. His mate was a cold hearted alpha who doesn't care if he up and died. Or so he thought....