In a Giyuu x Shinobu fanfic, the setting and plot can vary widely. Some might be set during the main events of the Demon Slayer universe, with them facing demons together. Others could be more of an alternate universe story, where they meet under different circumstances, like in a modern - day high school AU. The fanfic could also delve into their backstories and how those experiences shape their relationship. For instance, Shinobu's past with her sister could play a role in how she opens up to Giyuu, and vice versa for Giyuu's own traumas.
I would recommend 'Whispers of the Heart' for Giyuu x Shinobu fans. This fanfic focuses on their unspoken understanding. It's full of small moments that build up their relationship, like when Shinobu leaves a small flower on Giyuu's doorstep as a sign of her care. Also, 'Shadows and Sunlight' is worth checking out. It has a great plot that involves them having to go on a secret mission together and how that journey changes their relationship from colleagues to something more intimate.
It might be about Naruto snapping in terms of his personality. For instance, he could snap under the pressure of being the Hokage. He has so many responsibilities, and in the fanfiction, he might lose his patience with the politics, the demands of the villagers, or the internal disputes within the village. This could lead to a whole new arc where he has to figure out how to regain his composure and balance his duties.
The 'bnha izuku snapped fanfiction' might explore a darker side of Izuku's character. It could involve a situation where he reaches his breaking point and his actions deviate from his usual heroic self. This could be due to extreme stress, betrayal, or a series of events that push him over the edge. For example, perhaps he's constantly underestimated and finally snaps under the pressure of proving himself.
I'm not entirely sure specifically as it could be a very niche or new fanfiction. It might be a fan - created story related to something Canadian that has an element of a character or situation 'snapping' which could mean reaching a breaking point or changing suddenly in the narrative.
One common theme is the exploration of their relationship. Given their different personalities in the original work, fanfictions often focus on how they bridge the gap between them, like how Giyuu's stoicism and Shinobu's more cheerful yet calculating nature interact.