Naruto might initially be shocked and confused. He has always considered Sasuke as a friend, so Sasuke's sudden attempt on his life would be a huge blow. He may try to talk to Sasuke first, to understand why he is doing this.
One possible reason could be his thirst for power. He might see Naruto as an obstacle in his pursuit of greater strength. Maybe he believes that by eliminating Naruto, he can prove himself to be the stronger one and gain more recognition in the ninja world.
Sakura may initially be paralyzed by fear, but then her love for Sasuke and her own determination to survive could kick in. She might try to counter - attack in a non - lethal way, hoping to subdue Sasuke rather than harm him. She could also call out to their shared memories in an attempt to stop him from actually killing her.
In 'amy tries to kill sonic fanfic', it might be that Amy has been tricked by an enemy. The enemy could have made her believe Sonic has done something really bad. So, out of a sense of justice or revenge, she tries to take Sonic's life. However, it's all a big ruse, and Sonic has to figure out how to make Amy see the truth before it's too late.
I don't know who created this particular fanfic. There are so many Sonic fans out there creating various fanfics, and it's hard to pinpoint the creator without more information.
Another theme is self - discovery. As Sasuke tries to get Naruto, he also discovers more about himself. He realizes his own feelings and how Naruto has influenced his growth. In some fanfics, this is shown through Sasuke's internal monologues as he reflects on his relationship with Naruto.
One possible reason could be Sasuke's actions that Naruto deems too extreme for the safety of the village. For example, if Sasuke were to ally with a powerful enemy who plans to destroy Konoha. Naruto, being the protector of the village, might feel he has no choice but to kill Sasuke to safeguard his home and the people he loves. Another aspect could be a misunderstanding. Maybe Sasuke is framed for a heinous crime, and Naruto, without realizing the truth at first, believes he has to end Sasuke's life for justice. It could also be related to some dark power that has corrupted Sasuke's mind, making him a threat that Naruto has to eliminate to save Sasuke from himself in a rather extreme way.
One idea could be that Naruto and Sasuke are somehow transported to the world of Kill la Kill. They might get involved in the fight against the Life Fibers, with their ninja skills being a unique addition. Maybe Naruto's Rasengan could be used to disrupt the Life Fibers in a new way.
He could also try to dodge her attacks while still trying to reason with her. Naruto has a strong sense of loyalty and friendship, so he would likely be very reluctant to fight back against Sakura. He might keep asking her why she's doing this and try to get through to her emotional side.
In fanfiction, if Sasuke tries to steal from Naruto, it could lead to a major conflict. Naruto might be deeply hurt, considering they are friends (or frenemies depending on the plot stage). This could trigger a chase or a battle between them, and other characters might get involved to either stop Sasuke or take sides.