This will sound like a joke the way it begins: Kirk walked into Med Bay. But trust the narrator, it is not a joke. Kirk walked into Bones office. Bones was thumbing through a row of padds.
"Hey Bones." Kirk said.
"Yes?" Bones said, searching for a specific padd.
"How did you propose to your ex-wife?" Kirk asked.
Bones raised a eyebrow looking up from the row of padds.
"That is private." Bones said.
"Oh." Kirk said.
"But why are you asking?" Bones asked.
Kirk grinned.
"I am going to ask Spock to marry me with a family heirloom." Kirk said.
Bones blinked, stunned, at first.
"But. . . aren't you already married with Spock?" Bones asked, lowering his eyebrow.
"I want a wedding band to prove we are married!" Kirk said. "I am ready to spend the rest of my lifetime with this Vulcan through hell or not. I will haunt him in death, make sure he is happy, and enforce him to move on. Shouldn't a wedding band mean to a Vulcan that I will never ever leave his side as a ghost until he has found another mate to make him happy! I know Spock will be deeply touched by my death so I see this as a promise for the both of us." Kirk cleared his throat. "If one of us dies: one of us has to move on and find happiness in their life."
"Spock will outlive you," Bones said. "And I don't believe that Spock would take your last name under human marriage."
"He doesn't have to." Kirk said.
"What?" Bones said, surprised.
"I want proof of our marriage. For all to see. Whenever they look us up in the future after one of us are dead . . . They will see: ONCE MARRIED TO JAMES T. KIRK/SPOCK!" Kirk had a gleaming smile on his face. "Certificate and wedding band. That way, Spock has one way to remember me by. Not just memories and feelings and information." His voice lowered. "I just . . . want Spock to be happy."'
Also to save Spock's life, but that's for another time.
Bones put down the padds on the table.
"So you want a wedding band to mean something to this Vulcan," Bones said. "The one who says, "Small items are usually taken to symbolize a matter of great importance." when asking why a Klingon takes a locket instead of a dagger." Bones paused. "I suppose . . . that would be touching. If I were you, I find a good time to pose the question rather than later or some other ill time. Remember how Spock was when you died the first time around?" He had a grim look on his face. "You should really pop the question to the Vulcan soon. You are so reckless you are gonna die one of these days on a mission."
"Four years in space and I haven't died twice!" Kirk said.
"Arranging a wedding takes considerable time and effort from the both of you," Bones added. "It will be stressful, unless you have a good wedding planner."
"I am thinking of Las Vegas." Kirk said.
"Jim!" Bones said, in horror.
"Kidding!" Kirk said, with a shrug. "Bones, don't tell Spock about this. I want it to be a surprise. . . and until I pop the question. . ." He took out the engagement ring. "It is going to be in my pocket. All times. Through better or worse."