The official website for Servamp
has revealed that there will be original animation included in third through sixth volumes of BD and DVD. There will be 3 episodes of Sleepy Life of Servamp
and Hai ni Mamireta Shoukei: All the world's a stage
for the specials. The first special, which will be bundled with the third volume, will be released on November 25, 2016.
has been serialized on Comic Gene
by Strike Tanaka
since June 2011. Latest volume, which is tenth volume, has released on July 2016, and multiple drama CDs and character CDs have also released. TV anime is currently airing.
Source: Animate Times