You are the manager of Trapnest, It's kinda obvious that Ren's feelings towards you started to develop into something more because you were the only one who was there for him when he was dealing with his addiction. He also thought your voice is the most beautiful (something that Nana O wanted to hear from him about her voice) and found comfort in it.

Ren and you in the friendship is so beautiful, they truly cared for each other and were there for each other, wish it was recognized more often.

And now he engaged to Nana O. but realized he has fallen in love to you too, he depends on you so much but he never confessed to you, he love Nana O but you was his soulmate.