Valen Shadowbreath is a tiefling Weapon Master is first encountered in the rebel Drow encampment of Lith My'athar (Act two of Hordes of the Underdark).

Initially distrustful of the player, Valen nevertheless makes his services available, and is the romance option for female characters. Valen is a tremendously powerful warrior who makes a great tank for your small group. As a tiefling, or part-demon, he is constantly besieged by the violent nature of his infernal blood and his dark past. The player can choose to acquire Valen's true name near the end of the Hordes of the Underdark campaign. Before the final battle, the player then has a dialogue option to use Valen's true name to free him from his infernal taint, thus saving him from his own blood. If this is not done, Mephistopheles offers to do the same for Valen, and he will turn against the player unless a successful persuade check is made, he is compelled against his own will to fight with you (by use of his True Name), or a female player has built up a strong enough relationship with him.


I think we can discount that he is mafia I would say purly based on the character he is either a vig or a mafia. The only other option would be that he is a normal townie who can be turned good or evil comparing on who has his true name.