Doesn't the alpha needs sex right now? Why he hides this fact. Aren't they together?

He's afraid the Sejoon will think that's all he wants from him when he just got him to believe that isn't true and he loves him for him. He doesn't want to scare Sejoon so he's hiding it but it won't last long I'm assuming. Ruts are rougher than an omegas heat (๑•ㅂ•)و✧

That's what I thought too but it's also risky for his health like the heats omegas get. Aren't they also only reacting to their mates?