Prince Lotor is the only son to King Zarkon and heir to the throne of planet Doom in the far universe. On the surface, the prince is a loud mouth, show off that despises everyone around him. There are only five things that Lotor wants, to drink, lounge, to wield great power, possess Princess Allura of the planet Arus and rule her planet. In the original GoLion series, Lotor’s character is named Sincline (Shinkurain Kōtaishi). There are some great differences between the two characters, but the differences in Sincline explain the psychology behind Prince Lotor’s outrageous behavior in episodes 1 through 52, sometimes refferred to as "season 1".
It’s completely ignored in Voltron, but in GoLion Prince Lotor is half Drule, half human, which explains his good looks and possibly some attraction to human females. Tale in Golion goes into detail describing how King Zarkon impregnated a human and killed her with his bare hands for not agreeing to marry him. This adds more fuel to the fire, so when Lotor is constantly opposing his father and trying to kill him, being inherently evil has something to do with it but there is definitely good cause for hatred among the two.
The other twist to this is that somehow Lotor thinks Princess Allura looks like his mother or is compared to her in episode 15 entitled the sleeping princes. Beyond the two being blonde; I don’t see the resemblance even for an anime. This idea that Allura looks like his mother and this is the only reason why he is after her has been linked to an Oedipus complex. I strongly disagree.
Allura is pretty, she’s a princess, and Lotor is used to getting what he wants. It’s not easy to get her so he’s perplexed and desperate especially since every failure to capture or destroy the Voltron Force damages his reputation as a conqueror.
It’s all connected; power and Allura. Lotor has even spoken of her as his prize for defeating Voltron.
Keith often stands in the way of his many attempts to kidnap Allura or defeat Voltron and the two of them have many duels. Lotor and Keith are usually evenly matched. However, by the assumption given by English dubs, it is implied that Keith is superior to Lotor as a fighter, sticking to the American storytelling mantra that the villians can't be better fighters than the good guys.
Is it love; what prince Lotor feels for Allura? I don’t think so, or if it is love in Lotor’s mind, he doesn’t fully know the meaning of it. The man pulls a sword on her several times and chases her down like an animal. He intends to make her his slave serving him “night and day”. He wants her dressed like his harem slaves and dance for him when he calls. That is not love. He wants her as his property. She is the prize for power and he wants power even more than the princess.
In episode 16 (Love Bridge) Lotor even says, “Father would be pleased with the plan I have in mind. I intend to make princess Allura my wife, then I will be ruler of planet Arus without ever fighting a battle. It’s an amusing thought.”
The option to woo the princess is something that Lotor fails at because his is a brut of a prince with no charm skills to save his life. He pushes, he yanks, he hunts, and he hurts. He doesn’t know the meaning of the subtle approach when it comes to women. They are to be taken and used for his desires. That’s how he deals with everything in his world. Many of these displays are often diluted by the editing to omit the violence in the original series. In GoLion we see that Sincline, kills his subordinates at every chance to be cruel and unjust. He is a vile unstable villain that even kills a beautiful slave girl for spilling a drink on his pants. He kills his father and his grandmother without mercy. In episode 52, the American version shows Lotor killing his subjects and then says something to the effect, “it would have been satisfying if you weren’t all a bunch of dumb robots.” It is obvious that this verbal addition was placed there to cover up the fact that in the original GoLion, Sincline kills real live subjects including his second in command, Morgor.
In a few episodes in Voltron leading up to episode 52, Lotor’s journey to finally become king of planet Doom was concentrated and his obsession for Allura had diminished. His only mission was to gain power which he did. In the GoLion series, Sincline is killed in an epic battle in this very same episode but in Voltron he hits the water only because princess Allura’s voice is dubbed in and says, “He hit the water”. He lives on in later episodes enduring a small costume change wearing black gloves instead of white ones and donning an even darker hew of blue to his skin. Both creative changes attempting to make him appear more sinister. The largest change occurs in that he was given a new love interest in Queen Merla.
After episode 52 Lotor's feelings for Allura denotes that he actually cares for her safety than any previous episodes. There are several occasions he would protect her and she’d never know anything about it. All the while a very awkward love blossoming between Allura and Keith took center stage. Grrr!