Aziraphale! That's who Crowley charged him to protect. Then this will be an opportunity for Luo Binghe to figure out who he even is.

"Oh, that reminds me of something I meant to ask you. Shen Yuan and I spoke recently of who we are close to in the mansion, so that we might know to be good to each other's friends." Well, Shen Yuan is good to everyone, so really it was so Luo Binghe knew who not to manipulate, but that's beside the point. "You are very important to me—if there are people here you care about, I would like to know, so that I may see to their wellbeing, if it's in my power."