duolaamm Attention, you’ve double-posted the same message, so please delete the extra one. I imagine you ran into some difficulty when you tried to quote a user’s post in an attempt to reply to him.
As for your interest here, this is really a matter of perspective and personal choice. We’re in a fictional universe that takes some liberties with historical reality, introducing fantastical elements, all tied to Erastorm's story universe. It’s normal for the tone of the story to differ a bit from the historical period it draws inspiration from, while still sharing some similarities.
I see the capture of slaves, or prisoners, more as a consequence than a cause. Historically, Viking raids had several objectives (expansion, colonization, resources, trade, exploration, demographic needs, etc.). Helga, if I recall correctly, was once in service to another master who’s since passed away, and she was captured during a Bloody Bears raid back then when Ragnar still led the clan.
After the leadership change orchestrated by Candrid with Nick’s help, Helga joined the house of the new clan leader, Nick (MC), as a sort of concubine. You could still consider her a thrall, or even a sexual slave if you’d like, but it’s no longer that relevant now, since the relationship is completely voluntary and harmonious from my point of view.
However, if you’re looking for a master-slave relationship with full domination (including sexually), I’m not sure the game portrays it that way. You’ll have to decide if it meets your expectations.