#Xaela views would certainly vary in viewing their horns (such as the Dotharl) but I liked the idea of them contrasting

[tsunael]

— Headcanon

About an Au Ra's horns, and Tsuna's loss thereof:

I imagine an Au Ra's horns carry great cultural significance for them, and that significance would vary based on both region and clan. Though, for every Au Ra their horns are a source of pride: they determine when one comes of age, and grow with them until the day that they die (as sourced by the long horns the elder models have).

Word of God says they are are able to break and will regrow. I like to think that the Xaela would view losing a horn as a positive (tribe depending)-- it means they fought well and lived to see another day. Something akin to a battle scar.

For Raen, it is a great shame. They lost a part of their identity and a part of their heritage. It means they did not fight hard enough-- stemming from when they were taken in by the warlords of Othard purely for their fighting prowess.

For Tsuna, losing one of her horns to Zenos at the end of the final battle was a great blow to her mentality. She inherited her horn shape from her mother, and the loss of them makes the loss of her mother feel twofold. For a time, she experiences vertigo until her other horn is forced to be culled to match its twin.

However, with loss there gives rise to new beginnings. There's some symbolism of her outward-facing horns being broken in that she is finally able to accept love and take it for herself. Tsuna has always had a Hedgehog's Dilemma-- in every sense of the word. This is simply a physical way of breaking down her offense.

Basically... intimacy was near impossible before, and now she can smooch anything she wants. 'Once, she abstained, and now she devours' and all that. It also begins her journey of reflection of her culture and where she stands in it, and the slow process of undoing the harsh stigma that she was raised with. As a Raen, I also feel that there's a lot to say on her view of being a diaspora, but I'm not qualified to write that out at the moment.