Shell's memories are going to be perfectly accessible, but they will not come up automatically in response to stimuli unless the resulting Shell Bell is expressly open to it. They will keep Shell's hard-earned tolerance to pain, insofar as that's separable (Shell is quite sure that she'd be able to make a pentagon if another situation as important as getting ahold of Sherlock to mint Juliet came up). All of Shell's insights about Sherlock's importance stay. Her itchy discomfort with Sherlock not getting her importance will be folded into Bell's resignation to same. The merged Shell Bell will be comfortable referring to either past in the first or third person, but will default to using "I" for Bell and "she" for Shell. She'll torch, but that's the only supernatural property Shell's bringing to the merger; she'll retain all Bell's magic. Shell looks a little older, but not much; they'll go with that, as they think torching probably conflicts with actually aging and they don't think twenty is the ideal place to sit forever and whatever Shell is supposed to be is closer. They are omitting the nightmares, good riddance.
"Last minute questions, comments, reasons to expect this to be a bad idea in some way?" Bell asks.
Shell shakes her head. She is looking forward to not being a separate person anymore.
"He's right there, Nate," says Timer, "technically dead or not he's there - the more pressing issue is what we're going to -"
"I'm trying not to think about you," snaps Nathan. "If you - if you -"
"Yes, yes, you're afraid that I've been unfaithful, and also afraid that we got up to something while he was Downside, the only outcome you'd consider acceptable would be if I'd spent the last century celibate, how do you feel about making like Shell Bell and importing some of my more even-keeled notions? Sell it for me, babe, he's not gonna listen to me," Timer adds to the Joker when he sees the answering look on Nathan's face.
"Sweetie," says the Joker. "I love you. He's you, so I love him too. I don't wanna lose either of you, and I don't wanna make trouble between you the way it would if I hung around with both of you all the time. Shell and Bell got sewn up and they're just fine. If you're okay with it, and it works so you don't hate yourself afterward or anything, then I want you to."
Meanwhile, Golden and Shell Bell have relegated their exchange of information about exactly how Downside is shit to the brainphone.
"If that's what you need from me," he finally tells the Joker.
"I think it'll make us both happier," he says softly. "You know, I joke about how you'll have to get used to me, but I see how it hurts you to know what a slut I am and I don't want it to, sweetheart, I love you."
"Lack of opportunity," puts in Timer shortly. "Till he went Downside."
"Oh, Christ."
"You and he'd be happier with our joint self keeping my opinion on the matter."
"I am not at all confident that even an evil will be able to edit a mate bond," Golden says.
"Not the core of it. Just around the edges. The joined-up Nathan would still have it - like Alice has one - but it wouldn't come with the... monogamy clause."
"If it can do even that, that's unsettling," says Golden, "but I suppose whether I find it unsettling or not doesn't make it more or less likely to work. Joker, you're supplying the evil?"
"They should spend a little while working out a balance of the two of them. I'm mostly Bell and not Shell most of the time. We didn't want her memories to outweigh mine even though there were more of them."
Nathan nods.
"Yeah, I'll come up with the coin. Shell Bell, you wanna hit me, or should I wish up another one'a those agony beam gadgets?"
"Do you need ramp-up or can I just slam you with a hundred thousand?" Shell Bell inquires.
Bam. Unflavored. She holds for six seconds or until he says "when", since they'll want more than one for the merge as well as (possibly) the perma-minting.
He never bothered to wish himself another bandolier, so the coins appear directly in his hands, one two three fourfivesixseven before Shell's six seconds are up. He offers the whole handful to Golden.
"Thank you." (Covert declawing.) "Shell Bell, you've done a merger, perhaps you should also do this one." She wishes all but one evil onto her own bandolier and offers the other to Shell Bell. [I declawed it.]
"I'll stick around long enough for them to have their parameters worked out and then I'll do it, sure," agrees Shell Bell, tucking the evil onto her chain for the meanwhile.
"Gonna have to figure out how to square away my memories so my de-vampired Downside memories don't get completely lost against high-def surround-sound smell-o-vision," says Timer, waving a hand. "Maybe get us recall independent of vampirism like the other mint Bells have got."
"Do you want to remember being human here? Again?" asks Nathan skeptically.
"I don't see why not. We're going to fix the jealousy thing both directions, aren't we, we won't torture ourselves over - what was her name -"
"Calybrid."
"Yes, her, it won't matter, the Joker certainly doesn't mind her."
"...She's not in the -"
"I never looked her up," shrugs Timer.
"But I wasn't thinking so much of Calybrid."
"...Mmm. Okay, the kids could be a problem."
"You could put it - away, like I did with Shell's less pleasant memories," says Shell Bell. "Of which there are terribly many. They're all accessible if I want them. They don't intrude if I don't expressly invite them, and they're muted, a little, at a sort of emotional remove."
"...All right," says Nathan. "What else?"
"We want to torch," says Timer. "I haven't done it, but it'd be better than dying again, according to Eights it doesn't even feel like anything by itself."
"...All right."
"Oh, and as long as we're talking about editing the mate bond, let's not edit the part where you don't care what nether bits the Joker's got at any given time, he finds that inconvenient - don't look at me like that, I might not be all magically infatuated anymore but that leaves marks, he shows up and presto-changeo and snuggles up to me, what am I supposed to do?"
"God, I don't even know. All right," says Nathan.
"I think that's enough to go on," says Shell Bell, "unless you've got anything you need to leave out explicitly from one or the other of you - I had to get rid of some nightmares, some trembling, that sort of thing."
"Yes, please do let's get this over with," Nathan sighs.