You can only ask for advice in specific matchups. You have to talk to Allison&Nyx for advice on Shader&Cassius, and talk to Cassius&Shader for advice on Nyx.
Yeah it’s definitely a custom. Strange that it hasn’t happened to anyone else, I actually didn’t know there even was an eye choice until someone complimented my “undefined eyes”! Haha.
If jealousy is more important in book two, will there be another chance later on to have it set? Since you can’t have Cassius jealous of Shader in that you can only ask for advice as a package deal.