On Naito Longchamp and Mangusta
And, conversely, a bit on Tsuna and Reborn. From what I remember, Mangusta acts as more of an attendant than a right-hand man. He wears an outfit like he's a bellboy, and tends to be around cleaning up after Naito's messes, never attempting to teach him otherwise and seeming to harbor a steadily mounting resentment towards him. Of course, while his behavior would be the petty fuming of a child were they the same age and thus very reasonable, as an adult Mangusta has the dual responsibility of raising Naito to become worthy of being boss.
Because though it seems like Naito is heir, no one in the Family is particularly interested in keeping him both alive and reigning in his obliviously reckless personality. We haven't seen either hide or hair of Naito's parents, nor has Naito mentioned them much. He has a family but... does he though?
Naito's ignorance holds two different benefits for Mangusta:
Mangusta doesn't have to.... try. He doesn't really have to actually raise or guide him, just has to keep him alive. Because Naito is past saving, right? Poor Mangusta is doing everyone a favor by volunteering to clean up after that rotten brat, right? Isn't it enough that he lives another day?
As someone who's shown to be unable to communicate his own feelings and instead sneaks around problems (like the problem of Naito endangering himself and others), he uses Naito's flubs and his naivety as a way of fueling his own hatred towards the kid. He uses it to justify the lack of investment on his part.
In this way he mirrors Tsuna and Reborn: not Tsuna and Gokudera, as you may think right off the bat. While both Mangusta and Gokudera are their respective bosses "right hand’s" the roles they play interpersonally are functionally different. Tsuna is sullen, withdrawn and suspicious; Naito is naive, bright and loud and so, so reckless. They're both in the same class, the same age range, same positions, and they both have flaws that prevent them from being "proper" mafia bosses. How Reborn and Mangusta deal with this is entirely different (and both methods of "guidance" are worthy of criticism for being both cruel and unusual in different turns).
Mangusta cleans up after Naito. Keeps him in the dark. Naito fucks up, makes a mess, nearly dies. He runs wild and parties and goes to mixers and is an absolute mess, and Mangusta never tells him otherwise. Never pushes him to be better, never teaches him how to be better, never actually confronts and assuages the insecurities he KNOWS Naito has- he only exploits them while making sure the kid stews in them in order to escape future deadly encounters. He is CONSTANTLY looking over Naito's shoulder, he attends to the messes that needs cleaning and he enables Naito's recklessness.
This has the added benefit of allowing Mangusta to manipulate the strings from behind the scenes, shirking his duties while reaping the benefits of Naito's trust allows him to culminate power that will benefit exclusively Mangusta. Reborn, on the other than, is the opposite. He throws Tsuna into situations that he forces Tsuna to fix himself. He throws roadblocks in Tsuna's way and expects that he will overcome them- no matter how painful, traumatizing, or unnecessarily cruel they may actually be. He's intensely critical of Tsuna. His posture, his words, his actions. Who he knows and who he doesn't. Everything from what he's proud of to what he's insecure about. He exploits Tsuna's flaws to get the job itself done. Reborn is confident in his own power. He doesn't need Tsuna's power- doesn't need to hide behind the Vongola's resources, though he'll gladly take advantage of them in the heat of the moment. He has Tsuna's back, but does he though?
He guides, for sure, intensely so. In a way that makes Tsuna reliant on him in an ENTIRELY different way than Mangusta, though I don't especially think Reborn understands just what he's done. I can tell because of the way he's surprised when Tsuna helps him and makes an effort to ensure Reborn doesn't die. Reborn is ignorant in understanding how others see him, how he affects and relates to others because he's focused so intensely inwards.
That's besides the point though! Reborn teaches by forcing Tsuna to constantly confront his own flaws, while simultaneously building Tsuna a support network. Mangusta does the opposite, he avoids having Naito confront his flaws and keeps him isolated from others by exploiting his naivety and his insecurities.
TL;DR Naito Longchamp is being emotionally abused and Mangusta is exploiting Naito’s feelings for clout