Undefined Fantastic Object features three playable characters (Reimu, Marisa and Sanae), each with two weapon types. However, unlike Mountain of Faith and Subterranean Animism, the spell card (bombing) system from the older games (such as Perfect Cherry Blossom and Imperishable Night) has been reintroduced.
There has been a rumor spreading throughout Gensokyo since the early spring about a flying treasure ship. Since it brings good omen, the heroines race to see who will be the first to board the ship. But from the sky, there's a black, shadowy figure moving at a high speed chasing the girls...
Info from Touhou Wiki: http://touhou.wikia.com/wiki/Undefined_Fantastic_Object
This is the full game (Version 1.00a) not a demo!
This game came out just today at the Comiket 76 (C76), so of course there is no english patch yet. The external options file (custom.exe) has been translated already though, so I added that file to the torrent. (custome.exe)