When Natsu gets angry in the fanfiction, different characters have different reactions. Erza, being the strong and authoritative figure in the guild, would likely try to discipline Natsu in some way, but also understand that his anger often comes from a place of protecting his friends. Wendy would be a bit more timid in her approach. She might use her healing magic to try and calm Natsu's emotions, as she can sense the turmoil in his magic energy. And Makarov, the guild master, would probably give Natsu a stern look and a lecture about controlling his temper.
When Natsu gets angry in 'Fairy Tail' fanfiction, he often becomes a force to be reckoned with. His magic power can flare up uncontrollably. For example, he might accidentally set things on fire around him as his Fire Dragon Slayer magic responds to his emotions. Enemies are likely to face his full wrath, and he may charge into battle without much thought for strategy, relying solely on his brute strength and anger-fueled magic.
Lucy would be completely devastated. She and Natsu have a very close bond. She might go into a deep depression, constantly blaming herself for not being able to save him. Gray would be angry at first, feeling like he should have been there to help Natsu. Then he'd be sad and would probably vow to avenge Natsu. Erza would be strong on the outside but inside she'd be broken. She might try to keep Fairy Tail together in Natsu's memory. Happy would be inconsolable, constantly flying around looking for Natsu and refusing to believe he's really gone.
He might initially be in disbelief. Natsu is used to the loyalty among his Fairy Tail comrades, so betrayal would be a shock to him.
Some members might be sad at first. Lucy, for example, would surely miss him a great deal as they are close friends. She might worry about him constantly during his absence.
Natsu would likely be extremely hurt. He has always been loyal to Fairy Tail, so being betrayed would be a huge blow. He might initially be in disbelief, not wanting to accept that his friends and guildmates could turn on him.
Gray would be shocked at first. He and Natsu have a long - standing rivalry - but also a deep friendship. He might initially be angry that Natsu would just leave like that, but then he would realize how much he'll miss him. He might also feel a sense of loss for the guild as a whole, since Natsu is such an important part of it.
Lucy would be extremely distraught. She and Natsu have a very close bond. She might cry for days and even isolate herself from the rest of the guild at first. Gray would be angry and feel a strong sense of loss. He'd probably blame himself for not being there to help. Erza would be stoic on the outside but inside, she'd be deeply affected. She'd take charge of the situation, making sure Natsu's death was not in vain and that the guild stays strong.
Natsu would probably be very angry at first. He loves Fairy Tail like a family, so being kicked out would feel like a huge betrayal. He might go on a rampage, shouting and arguing with the guild members who made the decision.
He might be really angry at first. Natsu is a passionate character, and being kicked out unjustly would make him furious. He could storm off vowing to prove his worth and show the guild they made a mistake.
The guild members' reactions would vary greatly. Happy, being Natsu's closest companion, would likely be excited about the fanfiction. He might fly around the guild hall, telling everyone about it and adding his own little comments about how accurate or inaccurate it is. He would definitely be protective of Natsu's image in the fanfiction, especially if it's not a positive portrayal.