Mamo Williams is the original creator of the manga series Military! (stylized as Miritari!). This work is a Japanese four-panel comedy manga that was serialized in Ichijinsha's seinen manga magazine Manga 4-koma Palette. The initial series ran from 2009 to 2013 and was collected into five tankōbon volumes. A sequel series, titled Miritari! Otsugata, also written by Williams, began serialization in the same magazine in 2014 and continued until June 2018, releasing four volumes. The premise of Military! involves a high school boy who finds himself protected by a small tank unit from a neighboring country, forming the basis for its comedic situations.

The manga was adapted into an anime television series, also known as Military!, which aired in Japan between January 7 and March 25, 2015. The adaptation consisted of 12 episodes and one special, produced by the animation studio Creators in Pack, with Hiroshi Kimura serving as both director and scriptwriter. The anime retains the comedy genre of the original source material.

Beyond the Military! series, there is no widely documented information available regarding other original manga or anime works created by Mamo Williams. Consequently, details about a broader creative background, recurring artistic themes, a distinct artistic identity, or a more extensive industry significance remain undocumented based on available records. The known body of work is limited to the Military! manga and its sequel.