Luke, like his father, had eyes that reflected the bluest of skies. Luke's, when Vader looked at them would hold so much love, devotion and trust it would often drive him half mad with desire and lust.
While it had taken incredibly long for Luke's eyes to no longer hold fear- or even hatred for the man who was his father- as well as his enemy- it had been well worth it.
His son's eyes always were so expressive, especially at the height of passion. It was one of the few reasons Vader was fine that Luke hadn't been raised on Coruscant- surrounded by all of those back-stabbing politicians as well as Palpatine?
No, Luke would never have become the man he was if he had been given the upbringing he deserved.
So when the time came for his angelic son to go undercover in disguise and forced to dye his golden hair black and wear green eye contacts, the Dark lord of the Sith was none too pleased.
"We hope to see you again, soon Lord Skywalker." Admiral Piet said to his commanding officer, wishing the rebel turned imperial goodbye, clearly nervous about being aboard the ship without the only sentient being who could calm the Empire's second in command.
Luke gave the admiral a small smile, and shook his hand. While at first, Luke had shown minimal if any respect for anyone within the Empire- the last Jedi considered Piett a friend now.
"Same to you."
Lord Vader lead his son away from the bridge to their private hanger where their uniquely made ships were stored. Instead of their shared force abilities, it was actually mechanics that had helped the two form a relationship which was less rebel and imperial and more son and father.
As soon as the launch doors closed, Vader had pressed like against one of the cold durasteel walls- his mask thrown to the ground in the flurry of movement.
"You will finish your mission as soon as possible and return to me."
Luke looked up at him those fake green eyes making Vader's anger roll off him with the force but he could still clearly see Luke's devotion.
"I will, Father."
"If someone even looks at you, or even thinks of touching you, angel, I will destroy them." Vader's voice held no room for remorse or error. Luke knew the statement to be completely true- a mistake made by an officer when Luke first began living aboard his father's command ship made that perfectly clear.
He knew, without a doubt, that as long as there were two suns on Tatooine rising and setting that he belonged to his Father- body, heart and soul.
The look of absolute loyalty Luke gave made him decide that perhaps the contacts weren't so terrible.