It's not that I don't like you, it's just that I don't trust you yet.
Zanu takes a while to trust anyone that is not a fellow Blood Code. If he seems cold it's because he doesn't trust you, but he'll warm up to you sooner or later. It is harder for Zanu to trust those from The A.R.M.Y. and the Blood Code scientists. Once Zanu does start trusting someone they will never lose it and he will treat them as family. When Zanu trusts someone he is a fun loving guy that is always seeking something to do.
Has the Blood Code for lava/magma and water. He can cool the water as much as needed but can't use it as a direct weapon.
Zanu didn't have much of a chance since he was born with the Blood Code. He grew up learning that trusting other was commonly a mistake so will hardly ever trust anyone he doesn't already. He never met his parents since they abandoned him from birth and left him to fend for himself. This was common for Blood Code though, having one in the family was a disgrace. Beyond that Zanu has fended for himself and helped others when he could. Now he lives where he can and gets money when the opportunity arises.