MashMorgan is a great ship for many reasons, and the most important one to me personally is that there are so many angles to tackle it from.
Within the Fairy Calendar era, you've got a doomed romance. Whether they're lovers who know they're on a time limit, or people pining unwilling to start something at all, the fact is: this romance is doomed, and they both know it. They're from different worlds and times. Mash going home implies Tonelico's failure. Tonelico's success implies Mash's isolation. This love cannot change anything, but it mattered that it was here.
In the Queen's Calendar era, they're lovers to enemies. They're clearly both still fond of each other on some level. But that's not enough. They both stand on either side of that war, because they each want to protect different things. The agony! The pain! To be forced to fight someone you loved so! To know so intimately someone you must kill! Delicious. Of course, the most tragic part of this is that Mash didn't even get to kill Morgan herself. All of this, and they never got the catharsis of battle at the end. (Note: there is inherent eroticism in homicide trust me on this.)
Less obvious, but an aspect of their dynamic that I find really interesting is that... Mash is someone who is constantly asked by various nonhuman people for understanding. Goetia, the Lion King, Beryl, all asked Mash to understand their pov and goals. Because Mash, as a homunculus, fundamentally stands at the edge between human and nonhuman. She's legitimately these people's best shot at being understood. But through this pattern, Morgan is noticeably the one person who never asks for understanding. She explains herself, but that's it. What she does ask of Mash, however, is to find a good reason to fight Morgan. Cuz Tonelico just endured 3000 years of the most senseless and brutal violence- she's just fresh out witnessing her attempt to save Britain being destroyed on a whim. The only thing Tonelico asks is for their fight to actually have meaning for once. Don't face me just because I'm mildly inconvenient to you. Face me because you are striving for your own star. That, I will respect, and should you succeed in defeating me- I will be fine with that. (Also because Morgan long gave up on being understood, so she's not even trying with Mash, which is why I think it fucks that despite Morgan being a fucking brick wall, Mash still manages to know this girl better than most.)
Post-lb6, MashMorgan is a ship that is inherently haunted. Haunted by who they used to be. Haunted by what they had done. The ghost of Tonelico still exists within Morgan, and Mash knows it- you changed and you were wrapped into something terrible, but you are still the girl I love, you are not so different that I can call you a different person. And Morgan is haunted by her relationship with Mash- she doesn't, can't remember Fair Britain, but she still holds feelings and manneurisms pertaining Mash and has no idea where they come from. And past both these things- they are both haunted by the fact that they did try to kill each other. They were enemies. I spilled your blood. How do you rebuild a relationship after that? You can't go back to who you used to be. You can't remain as enemies now that you're forced to ally again. What then? Does Morgan remember? Is it better or worse if she does? Do they forgive each other? Is it better or worse if they do? You can't pretend it didn't happen. You can't go back to it either.
Additionally, Morgan is someone who fundamentally believes herself to be evil. She's a witch, a tyrant, a monster; she embraces all these titles wholeheartedly. Considering Mash is Fairy Knight Galahad, aka the purest knight of the round table, I can only imagine that Morgan has some thoughts about that. Even if she did fall for Mash- would she act upon it? When everything she touches turns to rot? Would she risks corrupting this epitome of virtue? (Note: Mash is a strong independant woman who can corrupts herself all on her own, which can be very funny or very tragic depending on how you want to write it.)
Now that last point is very much self-indulgent, but Mash is someone who, at the beginning of the game, barely had a sense of personhood- couldn't even understand Mozart when he said it was fine to be ugly of heart. She's changed a lot by now, and I think it should be shown with Mash being absolutely fucking deranged about Morgan's death. Mash has lost MANY people since the beginning of the story, but that trauma is shared with Guda. Morgan's however is her trauma and hers alone she ain't got no one to relate. I think she can handle grief with the grace of a crepe flipped right to the floor. AND that means you get neat Beryl parallels as well. Mash sees her own behavior as something reminiscent of Beryl's, and feeling SO bad about it, but what is she supposed to do? She's lost so much so fucking much can't she just have something to hold onto for once? Something more tangible than a memory? Anyways I think Mash should get to mishandle Morgan's corpse SO fucking bad.
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