To be honest I think it might be more the fact he is a vampire hasn't entirely sunk in yet. While he is a bit accepting of it at this point of time he is in the very early steps of becoming a vampire so he has yet to experience the pains of being vampire such as seeing his family and friends getting older and die. Because he has not experienced any of that yet as he is a newly born vampire I feel its more because he just turned into a vampire the pains and griefs he will ultimately feel haven't entirely sunk in.
I feel that both Bin and Mo lan di are going to go through emotional pains and character growth as the story progresses for Bin he is probably going to have to experience the pains of vampire before he truly has fully accepted his new life. And as for Mo Land Di I feel he is going to experience emotions he is not used to feeling and expressing which will make him into a better person due to his influence of being around Bin.
All in all I LOVE the cute moments we are having before the story takes its deeper parts of the drama that are to surely happening soon as the story progresses.
Bin He is quite accepting everything right now but I doubt he could keep that pretense for long