Ryuukishi is the sequel to Ryakudatsusha no In'en, which was released last month... or rather, Ryakudatsusha is a prelude/prequel to this game. However, the fundamental nature of the game has changed greatly. For one thing, this VN lacks the constant rape and mutilation scenes that were so a part of Ryakudatsusha...
... well not entirely. There is only one rape scene, and there are a few guro scenes. However, those scenes are not nearly as dominant as the ones in Ryakudatsusha. For those who liked the prelude, this game might be a bit of a shock to the system.
Anyway, this VN is based some time after the events in Ryakudatsusha, and Roy's manner and appearance have changed greatly. The grim adolescent of the first game has become a smiling young wandering apothecary, and his sword is now no longer in evidence. The setting is in a walled city at the foot of a mountain where a fire dragon lairs. Despite attacks by the dragon at irregular intervals, the city has thrived for several centuries, and its knights have systematized the process of sacrificing their lives to draw the dragon away from the civilians, knowing they can do nothing else.
The tone of this game, despite its frequently bloody/gory events, is far milder than Ryakudatsusha. There is some slice-of-life, which is mostly used for deepening the connection to the setting and heroines, as well as progressing the story. There are also some seriously good fights in this game, as Roy sometimes is forced to show his old skills in order to protect the four female knights who serve as the harem/heroines for the game (yes, it is a harem, lol).
The actual progression of the game is kinetic, with all the choices merely creating changes in individual scenes, rather than the story itself. The setting itself retains the darkness of Ryakudatsusha, while leavening the blood-soaked dough that is this particular fantasy world with lighter and gentler moments.