Interest in soil fauna biodiversity and their role in ecosystem functioning is increasing fast. Currently, it is necessary to know what drives the composition and dynamics of this hidden biodiversity to predict ecosystem-level consequences of environmental change via changing litter dynamics and invertebrate biodiversity. Soil fauna live in habitats composed of plant litter, the quality of which depends on trait afterlife effects of the plant community, although we still cannot connect plants and the soil fauna community solely based on litter traits as a food source. To plug this important gap, we propose a trait-based framework focusing on the concept that soil fauna live in “a house made of food”, i.e., a habitat composed of litter varying temporally and spatially in quality for shelter and reproduction, partly through their own feeding activities. To assess habitat quality of litter for soil fauna, we started to organize physical traits related to litter size and shape as well as litter traits related to plant economics spectrum. In this presentation, I will discuss temporal change in litter curliness through wetting and drying in association with litter water holding capacity as a representative of litter traits determining habitat stability for soil fauna.