They saw how Merlin and Ichigo wound up coming to their land. The senseless deaths and tragedies that took place. As well as a bit of stuff afterwards.
Including Ichigo's pure rage towards mini Merlin for hacking her arm off just below the elbow in an effort to disappear on her own instead of taking the other girl with her. They saw how deep the two girl's bond went even more when the other girl finally decided to not be pissed anymore and returned to mini Merlin's side and wrap her in her arms- both of them, shockingly enough.
Which indicated that the taller girl had a sort of regenerative ability not terribly unlike Meliodas's or Ban's own.
They saw Ichigo's pregnancy. The grief over the loss of her child, and how it helped to shape her into the person that she had ultimately become. And after that, there was only Merlin's memories of being one of the Sin's. Which included the two saying goodbye to each other.
"You'll come back right?" Ichigo asked as she and Merlin, in her present form walked hand in hand together along a river bank.
"Of course I will. Home is where the heart is, after all. And I feel no shame in saying that I'm leaving my heart with you." Merlin said, her red lips quirking up in a fond smile.
"Then I guess I should tell you that I'll lend you mine until you come back."
"Okay. I'm make sure to guard it carefully then."
The two of them slowly released each other's hand and separated a bit so that they could face each other.
"Be sure to visit every chance you get. You know, so I don't worry and come after you or anything."
"Okay. Don't go and get married while I'm gone. At least not to anyone that minds sharing."
"Ha, ha, ha. You're hilarious, Rukia."
"Maybe, but I'm not wrong. You've grown up beautifully Ichigo. Any man would be lucky to have you."
"And would likely die screaming within the first week. For funsies."
Merlin hummed and looked amused. "You do get bored quite easily. But at least your husband will be kept on his toes while he's running, screaming for his life."
The two of them exchanged grins as Merlin finally turned and started to walk away, tossing a loud, "I'd follow you to hell Ichigo! Now and forever!"
They couldn't see the other girl's face, but they heard her reply easily since it made Merlin's eyes tear up a bit. "And I would walk through untold horrors, blood, and hellfire just to to find you again."
After that, the memories ended and Merlin opened her eyes to look at them. Meliodas, Ban, King, and Gowther looked incredibly thoughtful about everything that they had just discovered, and didn't know what to think, much less say. While Diane was quietly sobbing her heart out.
It took several moments of silence. But finally one of them- Gowther managed to speak.
"The two of you have been through a lot since your arrival in this world." He fisted his hands in his lap for a moment. His knuckles turning white from how hard he was clenching them as he slowly said, "It must have been incredibly difficult for you both."
"It has been." Merlin said. "But if nothing else, everything that has occurred up to this point has simply made our bond that much stronger."
There was another heartbeat or so of silence before Meliodas finally seemed to snap himself out of his funk enough to say, "So...a baby. How are you guys going to manage that?"
Merlin gave him a wry smile. "We could do it like the first one."
The blond scrunched up his nose a little bit in distaste. Recalling the memory of how Ichigo had gotten in the family way the first time. Of course he didn't think that either of them had had any fun at the time. Since the whole thing had been sort of...an exploration. But then again maybe he was biased due to the fact that he'd seen Merlin's naked butt.
And frankly he didn't favor that method at all. Not if he was going to have to inevitably gouge his eyes out or something every time he walked in on the two naked.
"But then again, the reason that our first child didn't live probably had to do with birth defects. After all, between my own medical issues and hers- it's a wonder that the previous pregnancy lasted as long as it did."
"I didn't know that you had medical issues." He said, feeling slightly startled to be learning such an important thing now.
"I do. Well, we both do. It really can't be helped considering all of the battles that we both went through. However Ichigo's are minor compared to mine. I figure that I have at least another few years before I finally succumb to them."
Meliodas felt as if he'd just been slapped. His breath left him in a long and drawn out hiss as he stared at Merlin in horror. All around him he could hear the other Sin's...shouting, protesting- the sound of beer mugs hitting the floor and breaking.
He was only vaguely aware of Ban reaching across the table and grabbing the dark haired woman and yanking her up out of her seat looking as if he wanted to cry as he snarled, "Say it again!"
Merlin was oddly quiet. Her expression somber as she sighed and reached up and gently pried Ban's hand from her shirt and repeated herself. "I only have a short time left. Two...perhaps three years left. After that, I'll die."