Abstract: We present a sketch interface for interactively placing a 3D human character in a sitting position on a chair. The user first sketches the target pose as a 2D stick figure. The user can specify whether a joint will be attached to the environment (for example, the feet may be put on the ground) with a pin tool. Our system then reconstructs the 3D pose from the sketch figure considering the constraints specified by the user and the interaction between the character and the environment. This paper presents a user interface and a reconstruction algorithm that combines a genetic algorithm and a quasi-Newton solver to efficiently find a collision-free pose. An informal user study showed the effectiveness of our approach.