Zero's not exactly the type to 'confront', so I'm not sure what sort of conflict you are expecting. He pretty much just makes his presence known, tells them what he is and what he knows and that he's got his eyes alert to him and sometimes depending on the person that they can't really hide from him, even if they wanted to. Any 'conflict' usually comes from just making himself known and the vampire's reaction to him (it's usually never good since no one likes to be judged like that).
He has a strict rules of engagement that he follows, which since I know you know the series, as you play Aidou, you should be more than familiar with what his personal rules are. They are also nicely outlined in the latest chapter. Just like any other vampire, if you plan on doing something that would ping his 'vampire is baring their fangs' sense, to drop me a line as well. I'm sure you realize that though. I try to spend a lot of time learning the other vampire canons, both IC and OOC to help in my playing of him. Not only does it help me in knowing what Zero can expect, but he himself is very curious about the differences from different worlds.
There is a reason he really likes both Buffy and Faith, it's because they provide him that information. He'd possibly like Cherry for that reason too.
Don't be afraid to contact me if you have an idea or think there is something about Johnny that as Zero's player, I should know. I don't mind people fangirling their fandom, especially in instances where it is information that would be helpful for me in game to know when dealing with the character. In the meantime, I'll browse his wiki...since I like at least a base knowledge on the other vampires.