During the Clone Wars, Padme realizes how unhealthy her relationship with Anakin is for both of them, and leaves him (if she then gets with Riyo Chuchi or Duchess Satine, I'm hft-- Padme deserves a happier ending than she got). Anakin is devastated to the point of becoming self-destructive and non-functional, which really only proves Padme's point.

Obi-Wan supports Padme's decision, but it also hurts him to see Anakin that way, so he steps in to pick up the pieces, carefully but firmly dominating him. Anakin flourishes with this new outlet for his frustrations, which also satisfies his need for stability.

I'm seeing Anakin and Padme's relationship having been fairly vanilla (although she def called the shots), but Anakin having all manner of previously unexplored kinks, especially bondage, humiliation, and electro-stim. Bonus for Obi-Wan collecting versions of all the weird ways they get electrocuted in Clone Wars and adding them to their collection.

Tl;dr-- snarky, long suffering, but caring dom!Obi-Wan giving directionless, desperate Anakin the domination he craves after Padme leaves him.