Man, the Chris/Wesker dynamic is like a whole dissertation on toxic relationships. It's never just about the stars aligning, it's about two fundamentally broken forces colliding. The most obvious one is trust, or the brutal lack of it. Wesker is a walking, talking betrayal, and Chris's entire post-Mansion life is a reaction to that. So any story has to grapple with that core fracture. Does Chris forgive? Can Wesker be trusted even a little? The temptation to believe in redemption wars with the bone-deep knowledge that he'll probably stab you in the back.
Beyond that, there's this massive power imbalance that writers play with constantly. Wesker's enhanced, brilliant, and always three steps ahead. Chris is human, grounded in his physical strength and moral conviction. That creates a conflict of control. Is Chris just a pawn being manipulated again? Or is his stubborn humanity the one thing Wesker can't actually dominate? I've seen fics where Wesker tries to 'protect' Chris by keeping him caged, and Chris's struggle is always about retaining his agency and identity, refusing to be a pet project.
And the most heartbreaking ones explore the memory of what they were. That early 'comradery' in S.T.A.R.S. hangs over everything. The conflict there is between mourning what might have been a genuine connection and the horror of what Wesker chose to become. It’s grief, but for a person who isn’t even dead, just monstrously changed. The emotional pull is the ghost of that past against the bloody reality of the present.