Relationship

My perception of Bakura and Yami Bakura's relationship operates on several, unproven, premises. One, that Yami Bakura is evil, and Bakura is good, but the former is a powerful, elemental evil that can rightfully be called "villain", but the latter is good in a flawed, human way. Two, that both Bakuras are capable of interacting mentally, just like the "two" Yuugis. Three, that the physical and vocal changes that distinguish Yami Bakura are not meant to be seen by the characters.

Yami Bakura can vary his level of control over his host. When the "transformation" to Yami Bakura occurs, that is Yami's "full" manifestation. In this state, he has total control of Bakura's physical form and can chose whether or not to supress the real Bakura's awareness. If he does so, Bakura will have no memory of what Yami Bakura has done (such as in "Dark Eye Activates, Sacrifice"). In "The Metamorph Pot's Trap! The Flame Swordsman's Crisis!", Bakura was sealed inside the Change of Heart card, and thus was a seperate being and in full control of his actions. Furthermore, when Yami Bakura is in his "full" manifestation, he allows his true self to show.

In "Dark Flare! Red-Eyes Black Dragon", Bakura's facial expressions almost seem more like Yami Bakura's, even if his "transformation" doesn't happen. This could indicate that Yami Bakura can manipulate his host even if he isn't in "full" control. Perhaps this relates to how Bakura followed the gang after that episode, when it seems he's a casual acquantince: Yami Bakura was making Bakura follow them, perhaps even making Bakura belive he wanted to follow them.

Things become rather confusing in "Challenge from the Past! The Terrifying Zera!". Yami Bakura was in his "full" manifestation after Anzu was out of sight, but things changed at some point. Yami Bakura could be on the subconscious level of control, or merely acting the part of his host, an ability that would be quite useful.

Now for the pure fanfic territory. I'd like to believe the two Bakuras have a long history of interaction. Because Bakura's mental efforts can make Yami Bakura's control harder, Yami Bakura tries to break his host psychologically, usually by trying to convince the boy of the hopelessness of his situation, attacking Bakura's perception of his own goodness, or trying to make Bakura feel he enjoys the power Yami Bakura gives him. Though going through a lot of angst and pain, the real Bakura eventually "prevailed". That is, he did not yield to his alter ego but instead resolved to make what efforts he could to keep Yami Bakura away from others, and not worry about what he couldn't control. These efforts mainly consisted of distancing himself from others by being quiet and avoiding people. Despite himself, Bakura still wants for companionship, and it was easy for Yami Bakura to make Bakura feel "safe" with the Yuugi and his friends. Though Bakura has his suspicions of the role Yami Bakura played in forming that bond, he considers his loyalty to his friends genuine. However, recognizing the danger to Yuugi and the others, Bakura still doesn't socialize with them as often as he'd like.