Big Eyes, Small Mouth
BESM, short for "Big Eyes, Small Mouth", is a table-top RPG created with the aim to capture the feel of anime and manga in its gameplay. Originally created by the now defunct Canadian gaming company Guardians of Order, now owned by White Wolf's indie sub-company Arthaus.
BESM has been praised for its use of the Tri-Stat system, though the first appearance of the term Tri-Stat system did not appear until the release of BESM 2nd-edition. The Tri-Stat core mechanic was later printed in a free-use document called Tri-Stat dX.
The first edition of BESM was a bit of a clusterfuck, as it was GoO's first release, but unlike many companies' first releases, it was still playable and fun. BESM saw many revisions via fanguides that packed in a modified version of the core BESM rules and special setting specific character creation rules. Some of these included Dominion Tank Police, Sailor Moon and Tenchi Muyo, the last of which was sort of a working draft of the game's Second Edition.
The Second Edition of BESM saw the removal of rolled base stats, and rebalanced point costs for attributes. It also reworded many of the rules and abilities to make them clearer and easier to understand. Later came a revised book that updated the core rules with three years worth of errata, as well as the crunch from many their various genre books, such as Hot Rods and Gun Bunnies and Cute and Fuzzy Cockfighting Seizure Monsters.
After the release of the revised second edition GoO proceeded to release meta-settings, such as Cold Hands, Dark Hearts (a weeaboo take on the World of Darkness), Uresia (a dungeons and dragons-like setting) and Centauri Knights (a sci-fi/space opera setting). Second edition also saw a boom in GoO's Ultimate Fanguide line, obtaining the licenses for Slayers, Utena, Niea Under 7, Dual and Hellsing.
During the time of the revised second edition, to jump on the bandwagon of the d20 SRD craze, they released an abhorrently broken BESMd20. It also saw the creation of Mecha d20. There were also d20 fanguides created for Hellsing and Trigun.
The game is currently dead, the most recent iteration being the third edition of the core Tri-stat system-based game. The third edition was a drastic departure from editions to come before it, the creation of which bankrupted the Guardians of Order the same way many fa/tg/uys hoped the creation of Dungeons & Dragons 4th Edition was going to do to WotC. Its biggest change was a reconstruction of the point system, and inversion of the dice mechanic, from a roll-under to a roll-over system.
BESM third edition was licensed and its printed stock was purchased by White Wolf's imprint Arthaus, who went on to sell the stock and keep a token subpage on their website dedicated to it for a time. Currently there are only a scant few traces of BESM anywhere on White Wolf's main site, and they made it clear that they are not intending to support the system in any way, effectively killing the game. The White Wolf wiki has two entries about the game, one detailing the history game license, another the setting seed from third edition.
And no, this has NOTHING to do with BDSM.