One possibility is that Amy would turn her grief into motivation. She could take on Sonic's role in protecting their world. She'd train harder, be more vigilant, and vow to defeat any threats that Sonic used to face. Her reaction could also involve her reaching out to Sonic's other friends, and together they could form a stronger bond in his memory, while also dealing with their own individual griefs.
Shadow could also play a role. He has his own complex relationship with Sonic. His reaction to Sonic's death might be a mix of respect and perhaps a sense of loss of a worthy adversary. He could either help or be a source of conflict depending on how the story is written. And of course, the Chaotix detective group could be involved in investigating Sonic's death as well.
I'm not sure about its popularity. It could be popular within a niche group of Sonic fans who are interested in more extreme or non - traditional storylines. However, it might not be as well - known to the general Sonic fanbase as it has a rather specific and somewhat disturbing concept.
I'm not sure specifically as I haven't read this particular fanfic. But it could potentially be a story where Amy, a character, does something that causes Sonic to have a serious injury like a broken back. It might be a very dramatic or action - filled plot within the Sonic fanfic universe.
Sonic and Amy's relationship is quite interesting. Amy has a huge crush on Sonic. She is always chasing after him, her love being very passionate. Sonic, on the other hand, while he may not always show it in the most obvious way, he does care about Amy. In their adventures together, there are moments where Sonic's protective side for Amy shines through, which could be seen as a sign of his underlying feelings. Their love story is one of the unspoken yet deep - rooted emotions in the Sonic universe.
Well, Ruby would probably be really enthusiastic about it. She's always open - minded and would likely find the creative ideas in the fanfic interesting. Weiss might be more critical, as she has high standards. Blake could be intrigued by different takes on the characters' backstories, and Yang would probably enjoy seeing some epic battles in the fanfic, but also might not like if her character is made to look weak.
It's hard to say whether the 'amy kills sonic fanfic' is popular. The Sonic fanfic community is diverse, with fans having different tastes. Some might enjoy exploring the darker and more controversial storylines like this one, but it could also be that a large portion of the community prefers the more traditional, positive stories. So it might not be as mainstream popular as some of the more typical Sonic fanfics.
There are many interesting fanfictions about Sonic and Amy's love. Some focus on their adventures together where their love slowly blossoms. For example, in some stories, they might face a powerful enemy together and through that experience, their bond deepens.
Tails could be one of the main characters. He might play a role in helping Amy realize that her chasing Sonic isn't healthy. For instance, he could give her advice based on his own observations.
For Amy, she could become more understanding of the 'evil' or opposing side. Instead of just seeing Metal Sonic as a bad guy, she might learn to look deeper into his existence as a creation. This could make her more empathetic in general.