Mirayuki’s true nature

The offer is tempting. Tempting, very tempting. 

By joining the Basilisk Order, I would gain access to a vast network of resources and power. As far as I know, their influence extends across every nation and kingdom in the world. Finding my sister would be much easier with their help. And furthermore, Mirayuku's position as an Ocular would definitely aid me a lot.

However…

"I simply cannot accept just yet."

"May I know the reason?" 

"There are things that need to be considered, Mira."

After all, joining just for the power and benefits would be foolish. Besides the fact that the Order has absolute control over the black market and even the Adventurer's Guild, I know very little about their true nature. What do they do on a regular basis? Do they abide by any moral code? What are their goals and ideology? Do they engage in horrible acts such as the homicide of innocent people or slavery?