Marazhai Romance Guide
Gender lock: Any gender. Marazhai is the one male companion a male Rogue Trader can romance, and he reciprocates a woman just as readily.
TL;DR: Recruit Marazhai in Chapter 3, keep him alive, and agree with his cruelty when the game offers the chance. Save him at the end of his first Companion Quest and the romance carries through to its final scene in Act 5.
The short version
This is the dark one. entity:marazhai is a Drukhari, and the relationship runs on the logic he lives by: pain, dominance, and a partner who walks toward danger rather than away from it. There is no conviction requirement to start, but flinching from violence will lose you the romance. Refuse danger too often and Marazhai walks. He wants a brave partner, and he means it in the bloodiest sense the word allows.
Two roles open up for the player here, Dominant and Submissive. The choice is changeable early on, so an experimental answer in the first scenes does not lock you out of the other path later.
Recruiting Marazhai
entity:marazhai joins in Chapter 3 during the mission "The Chasm." You propose an alliance to him alongside the Bloodstained Proselytes, then insist the offer still stands during the arena fight against the Wych Cult. He switches sides and joins your party after the battle at level 29. Keep him in the retinue: the romance cannot begin if he is dead or left behind.
Romance steps
Keep him alive and in the party. Let entity:marazhai live and bring him through Chapter 3 with you. Everything downstream depends on him surviving his recruitment arc.
Agree with him. Marazhai responds to a Rogue Trader who shares his appetites. Show interest and side with him when the dialogue allows. In practice that means the cruel option, the one that makes people suffer or ends them outright. He warms to a partner who reaches for the knife.
Chapter 4, his first Companion Quest. Complete it, and at the decision point choose to save Marazhai rather than killing him or letting the daemon take him over. This is the hinge of the whole romance. The other two outcomes end any chance of a relationship.
The quarters scene. After you save him, a scene triggers in your quarters built around a promise he once made. Let him agree to become your guide. The romance settles into its shape here, and the Dominant or Submissive dynamic takes hold.
Hold the course to Act 5. The romance resolves late, with the epilogue scene playing in Act 5, so the steps above are the foundation rather than the finish. Keep choosing the brave, bloody-minded options across the chapters between, because the same trait that drew him to you is the one that keeps him.
Breakup warning
Marazhai seeks a brave partner, and the game enforces it. Refusing danger too often causes a breakup. If your Rogue Trader keeps backing down from a fight or choosing the safe road, expect him to lose interest and end things. Play him a coward and you lose him.
The reward
Finishing the Marazhai romance grants the talent Taint of the Heart, which carries stat bonuses. The relationship leaves a mark on your character sheet as well as the story.
One more thing worth knowing before you commit: pursuing Marazhai angers entity:abelard, your oldest and most loyal retainer. The two cannot share your favor comfortably, and choosing the Drukhari costs you something with the man who has stood at your side since the prologue.
Exclusivity
You can keep more than one romance alive at the same time, up to the quest The Lord Inquisitor and The Lord Captain. After that beat you choose a single love interest and the others close. If Marazhai is your pick, make sure your earlier flirtations have not already soured him, and commit to him cleanly when the choice arrives.
For where Marazhai lands as a combat pick and how to build his Drukhari assassin kit, see the companion tier list and the builds hub. For the other retinue flames and the rules that bind every romance, start with the romance guide.