[quote=@6slyboy6]
[@Sinerathin] Well thanks. I told you how I am a TOTAL noob for warhammer 40k. Tho if I change to mercenary class, what will that affect? Also I would have made a completely different character for the tamer. COrrect me on the points I am wrong please.
[/quote]

You wouldn't have to change much. In fact, I'd say your current backstory for your character pretty much already makes you a Mercenary type character :)

Classes in this game are generally just a description of your character's usual profession, but what's contained within a class can be very broad and mercenaries are one category who are so wild and diverse one could hardly ever generalize them. Everything from armor, appearance, clothes, history, disposition etc tends to be very idiosyncratic. 

And yes, for it to be reasonable to be a leash holder for such a beast, you'd most likely have to be in the Adeptus Mechanicus.

[quote=@Jbcool]
40K?! I am interested.

Sanctioned Xenos character, any chance?
[/quote]

Not really. It'd have to be a human character, though it may also include humans with modifications, minor mutations, psykers or some human sub-category.

But other than that, it's pretty free what you want to be :)