They might like fanfiction because it offers new perspectives. Fanfiction writers can take the existing characters of Nico and Thalia and put them in fresh situations, which can be really exciting to read.
Maybe in the fanfic, Percy has some actions or characteristics that Nico doesn't like. For example, Percy might be too self - centered in the story, which goes against Nico's values. Or perhaps Percy has something that Nico desires, like more popularity or a closer relationship with a certain character, and that envy turns into hatred in the context of the fanfic.
Maybe Nico has his own view of the characters. He might think that the 'nicecery' in the fanfic distorts the real relationship or personalities of the characters, so he hates it.
Well, in fanfiction, the idea of Percy being possessive of Nico can be explored in many ways. It could be a sign of his insecurity. Perhaps Percy has lost important people in his life before and is afraid of losing Nico too. So, he becomes possessive as a way to keep Nico close. It can also be a way to show his evolving character. If the fanfiction is set in a world where there are threats, Percy's possessiveness might be his way of ensuring Nico's safety, like he doesn't trust others to protect Nico as well as he can.
In some fanfictions, their relationship might develop because of a common enemy. The threat of this enemy forces them to put aside any differences and work together closely. As they do this, they start to see the good in each other. Nico might see Percy's leadership skills, and Percy might see Nico's hidden strength and loyalty. They gradually become closer friends or even something more, depending on the nature of the fanfiction.
In the fanfiction, Percy might use his demigod senses. Since he has been in the casino before, he knows the layout and the tricks it plays. He could be searching for any signs of Nico's presence, like his unique demigod aura or any items that Nico might have left behind as he moved through the casino.
Well, 'nico nico visual novel' could be a form of entertainment where players/readers engage with a story presented in a visual format. It might include various genres like romance, mystery, or adventure. The Nico Nico aspect could imply that it has some connection to the Nico Nico community, perhaps user - created content or a specific following within that community.
I'm not sure of the most popular specific 'nico nico visual novel' titles off - hand. However, some popular visual novels in general might give an idea. Titles like 'Clannad' are well - known, but it's not clear if there are exact equivalents within the nico nico realm.
Nico might be initially shocked. He could feel a deep sense of anger towards whoever was responsible for Percy's abuse. Then he would probably become very protective of Percy, vowing to keep him safe from any further harm.