Big Eyes, Small Mouth (BESM) is a tabletop role-playing game originally produced by Guardians of Order in 1997 that was designed to simulate the action of anime and manga.

The title alludes to the common anime drawing style of characters with large expressive eyes and comparatively small mouths.

Players roll two 6-sided dice, add 10 to the total and then divide the resultant sum between Mind, Body, and Soul, against which all action checks are made.

Soon after that, RPG writer David L. Pulver began writing supplements for what was essentially a fairly simple game, adding a detailed system for the creation of mecha with his book Big Robots, Cool Starships.

In addition, several genre based supplements were published for the game, as well as two original settings: Centauri Knights and Uresia: Grave of Heaven.

Mark MacKinnon announced that as of August 1, 2006, Guardians of Order was going out of business, and that "BESM Third Edition is finished and ready for press.

On April 29, 2019, Dyskami Publishing Company announced that they had entered into a worldwide licensing arrangement with White Wolf Entertainment to produce a new edition of BESM.

[6] After a successful crowdfunding campaign on Kickstarter, Dyskami Publishing Company released complete PDF files of multiple BESM Fourth Edition products to the product's backers on December 23, 2019, including the core and Naked RPGs, game screen, adventures, character folio, and sample characters.

[7] The BESM Fourth Edition product line was sent to the printer in January 2020 and had its worldwide consumer and retailer release in October 2020.

[9] To coincide with the digital BESM Fourth Edition launch, Dyskami Publishing Company also announced plans during the Kickstarter campaign to launch a community content PDF program on DriveThruRPG called Tri-Stat Emporium, whose name alludes to the Tri-Stat System generic role-playing game system used in all editions of BESM thus far.

Although the books were usually well put-together and almost always featured many full-color pages with stills from the series involved, many fans believed the information provided in certain guides was incomplete and unreliable.

Due to licensing consideration, the three-volume set of fan guides for Slayers does not include any information from the movies and OVAs distributed by ADV Films.