Personality 

Vax'ildan appears cold and unapproachable, quiet and withdrawn, only speaks to those he needs to. He is very blunt with his words and will not lie to someone to avoid hurting their feelings. He can be careful with his words, not lying but carefully selecting the correct words to avoid offending someone. Hes aware that he can gain any favours if nobody likes him. Granted, if someone needs that little bit of protection, they shouldn't be in his life. He is a harsh leader and hardly shows any softness towards others unless directed towards his sisters. 

He does have the ability to turn that around and come across as very open, charming and social if his job needs it. Vax is aware

But he also have the ability to turn all that around and come across as very open, charming and social if his job needs it. He knows that with being and assassin that sometimes getting close to someone is needed, and its difficult to get that if hes cold and unapproachable. Basically he has his normal self and then his work personality. 

Vax works hard in his life, he strives for power and hopes to fall into a high rank within the scourge. For him work comes before everything else. If he was made to pick over that and his family work would come first all the way. Plus he has very little respect for his mother and father and look up for the leaders of the scourge over them. As said before the only two lions who have a soft spot in his heart are is sisters Vex'aliha and Velora.