VanillaWare is a Japanese company who specialise in creating various platforming/action games based on Japanese mythology with a unique 2D oriental style. Their main series consists of Princess Crown (Created while the team were still working for Atlus), Odin Sphere (Probably their most well known game) and Muramasa: The Demon Blade (currently avaliable for the Nintendo Wii). The only outlier to this successful formula is GrimGrimoire which was a console RTS game done in a style never seen before in video games (A good way to explain it would be similar to that of Swords & Soldiers for PSN & Wii Ware). Despite VanillaWare’s games consisting purely of original titles, the CEO of the company George Kamitani has stated that he has considered a sequel for GrimGrimoire for a long time, explicitly stating that he wanted online play if a sequel were to ever come into fruition.
This proposed sequel may not be entirely made of fiction. In Japan, there is an unnamed company who is responsible for the bulk of localisation and voice work for various Japanese video games. In their credits section, not just do they have the credits for their work on Grim Grimoire, but they also have the credits for their work on Grim Grimoire 2. The game is listed as a PS2 game so unless they plan on taking the Persona 4 route, either the project has been scrapped or it has been shifted to another console (hopefully the latter considering that VanillaWare isn’t really doing much right now… unless that rumour about Muramasa 3DS and Muramasa/Odin Sphere HD ports are true).