Chestnuts get sweeter and softer the more you slow roast them over a low heat just like the slowburn that is the novel :)) but if you are cashing in on the chestnut metaphor, there's another interesting interpretation of their relationship.
In the shoshimin series, there's this comparison between marron glacé and kurikinton: they might be the respective chestnut desserts of their countries, but the method to prepare them couldn't be more different.
The chestnuts in marron glacé are dipped in sugar syrup again and again and again to allow the sweetness of the sugar to permeate throughout the chestnut, so much so that the chestnut itself becomes sweet—completely different from its original bitter and astringent self.
For kurikinton, the chestnuts are boiled and mashed down to a paste before cooking them with sugar. Then, a tea towel is used to twist them into the desired shape that is more pleasing than mashed paste and present them accompanied with tea in tea ceremonies.
It symbolizes two ways you can fit into society: surround yourself with normal people until normalcy eventually becomes a part of your identity, like the chestnut-soaked sugar in marron glacé. Or get broken down completely and normalcy blended in before taking a new shape, but at your core you are still chestnut with a bit of sugar added, not an amalgamation of chestnut and sugar syrup.
I guess you can use this metaphor with both novel Lloyd and Javier. Lloyd represents the kurikinton method—always keeping himself separate from the Frontera people because he knew he was from a different world + stole their young master's identity = doesn't belong with them chestnuts. Even after Javier, unbeknownst to him, found out about his identity and constantly wore a 'i know everything already so trust me and fess up' clown hat, Lloyd would keep everything under a tight lid. He'd rather break down like last night than share his burden with Javier when he confronted Lloyd with his clown hat the next morning (tged novel ch383 + 384).
Lloyd kept that secret to the bitter end and only finally faced the count & countess when he had to come back to Lorasia in his own body. Like the kurikinton, he had been boiled and mashed down and twisted into something that looks completely different from his original chestnut form, but he's still Kim Suho, who was saved by Javier showing up unannounced and bringing him back home at the end of the day.
Javier, on the other hand, is unapologetically a marron glacé. Expensive, time-consuming to make, a decoration that overshadows the confectionery it's on, pleasing to the eye, and you get sick of it after two or three bites. Originally, he's someone with firm principles as befitting of a knight, but he's been observing Suho for so long that he came to understand that while he lied to the count and his family, he's apologetic and his actions have only benefited the fiefdom. Doesn't mean it's all water under the bridge—Javier was the only one being honest in their relationship this whole time.
At this point, Javier was still a rigid chestnut that didn't let the sugar syrup consume him just after one round, but the more he observed the fake again and again he began allowing the fake to change him, and in the end was even willing to die for him despite the fake not having his sworn fealty as a knight. He came to hope the fake would share some of his burden with him and come clean already. At the end, he wanted to know if the fake was happy wherever he was reborn at the expense of bearing out his feelings to the entire fiefdom, and even gave Verkis' head a wellness check-up, something unthinkable to the him after Hell arc since Verkis' wrath could turn to the fiefdom if he pissed him off. He'd changed from a bitter chestnut to something overflowing with sugary syrup when bit into while still maintaining his appearance as a shiny chestnut.
They are both each other's chestnuts and sugar :))) how disgustingly sweet :))))
edit: was going to make this post a comment to the og post but it got too long
sorry for the crappy image quality but the left one is marron glacé and the right one is kurikinton
