OK, it's got some (poorly done, btw) guy-on-guy action. I can't imagine any other reason anyone would watch this movie, and even that doesn't save it from being too silly for words. Perhaps if you've read the manga it's based on you can fill in some detail from that, but watched on its own, as I did, it's the worst sort of shallow "Plot? What plot?" anime dreck.
It also showcases the strange anime phenomenon of the "aggressive" lover; ie near-rapist. Guy 1: "No, honey, I don't wanna". Guy 2 turns into wolf and forces the issue: "C'mon, you know no means yes!" Guy 1 caves, winces, bites his lip, and ultimately enjoys himself, but what a message! Makes me wonder about relationships in Japan, as this seems to be a consistent theme in this genre.
Bottom line: the script, such as it is, appears to have been written by brainless 13-year-old school girls. Animation quality: fair to poor.
If you want decent yaoi, try "Angel Sanctuary" or "Fake." If you like the "agressive lover" bit, scare up a copy of the harder-edged "Ai no Kusabi".
If you want really good anime, watch "Cowboy Bebop" or 'Trigun" and use your imagination for the naughty elements. If it hadn't been for those two shows, I wouldn't watch any anime at all.