Can confirm the game freezes after the initial loading screen if not connected to the internet. I can't see an universe in which this was a good idea for DRM.
This isn't even DRM. If that was the case they'd have you make an account or otherwise verify that you purchased the game. What this looks like is Tasofro attempting to prevent non-Japanese players from playing online with their "lobby" feature. However, if that was the case the game would just prevent you from using the lobby if it detects your IP as non-Japanese.
Upon startup, once the title music begins to play, the game connects to flets-st1180.kamome.or.jp on TCP port 8888, followed by TCP port 443. Very few data is sent through these sessions. If for whatever reason these connections can't be made or are terminated prematurely, the game will freeze shortly afterward. This means that an internet connection and access to the aforementioned server is required to play the game, whether it's single-player or IP-based player-to-player.
This behavior seems more like regional lockout, since regions that are on a blacklist won't be allowed to play the game at all. Perhaps it's some form of anti-piracy measure targeting regions with high piracy rates? Regardless, many people can personally confirm that the game works from U.S.-based IP addresses, though I still wouldn't recommend using the online lobby due to the game explicitly stating that the feature is to be used by players in Japan only.
Addendum: The launcher that patches the game to ignore DLL hooks such as the one used by nVidia hybrid graphics still works with this latest version.
