Well, unlocking Pure Fiction Star Rail can be a bit tricky. Sometimes it involves achieving high scores in specific challenges, and other times it could be tied to your progress in the main game quests. You should also check the game's official guides or forums for the most accurate and up-to-date info.
I don't recommend looking for such content. Most visual novels are intended for entertainment without involving inappropriate or adult-oriented material.
I think Tera Story is good. The graphics are nice, the gameplay is fun, and the story keeps you hooked. However, some might find it a bit challenging or not to their taste.
Another way could be through multiplayer achievements. If you play well in multiplayer mode and reach certain milestones, like winning a certain number of races or having the most points in a session, it might unlock additional characters.
Unlocking all the content in Phantasy Star Portable 2 Infinity Story is a bit of a journey. Start by thoroughly exploring the main story. As you progress, you'll come across various events and challenges. Completing these with high performance, such as not dying during a difficult mission or using specific strategies, can unlock additional content. Some content might be tied to collecting a certain number of specific items. So, keep an eye out for rare drops during battles. Additionally, interacting with all the non - player characters and fully exploring each area can also reveal hidden unlockables.