I have created this character for years ,you can find my reply on here ,I use instant meshes for topology from a sculpt mesh Instant field aligned meshes - #75 by imdjs
the dotted lines is connected to a empty object ,which is the parent of whole scene.
the mesh is not hard to create but the rigging setting is hard to make it perfect , I still improving the rigging and weight map, textures,matierial,driver, etc.
here are some sculpt videos I made: