1. A digital content editing apparatus that edits a content having associated license information or multiple content including a plurality of the contents, comprising: a reuse license processor configured to obtain a spatial constraint from the license information defining a grant for a reusing operation of the content or the multiple content given an instruction to reuse, the spatial constraint indicating a positional relation on a reuse screen at the time of using the content or the multiple content together with a constraint object content or a multiple constraint object content other than the content or the multiple content given the instruction to reuse; an instruction generator configured to generate an operation execution instruction of disposing the content or the multiple content according to the positional relation on the reuse screen defined in the spatial constraint obtained by the reuse license processor; a reusing unit configured to reuse the content or the multiple content based on the operation execution instruction generated by the instruction generator; and an editor configured to edit the content or the multiple content reused by the reusing unit.