Source on Batarian society?

Hi y'all!

I am planning to write a short story set in the Mass Effect universe (for fun mostly, we are a few for fun writers who share stories around) and find the concept of writing about a Batarian merc unwittingly helping the Illusive man start Cerberus through a series of escalating missions raising xenophobic sentiments in human space.

I struggle a bit with the Batarian MCs motives though and thinks it's largely because we haven't really gotten a very nuanced picture of Batarians as far as I am aware.

Is there any descent source on how Batarian society works a bit more in depth despite being a caste-system and open towards slavery, the whole "Social standing as a subscription" thing?

The Wiki is quite sparse on the details of their caste system and I am open to more sources :)