Lillia and Treize (リリアとトレイズ, Riria to Toreizu) is a Japanese light novel adventure series written by Keiichi Sigsawa, with illustrations by Kohaku Kuroboshi, starring the children of the characters from Allison.

There are six light novels in the series, published by MediaWorks under their Dengeki Bunko label.

[1] Lillia and Treize began as a series of light novels written by Keiichi Sigsawa and drawn by Kouhaku Kuroboshi.

The manga takes its story from the light novels that preceded it, and is illustrated by Hiroki Haruse.

The first bound volume was published by ASCII Media Works on April 26, 2008 under their Dengeki Comics label.