luatexja.jfont.define_jfm {
   dir = 'yoko',
   zw = 1.0, zh = 1.0,

   [0] = {
      align = 'left', left = 0.0, down = 0.0,
      width = 1.0, height = 0.5, depth = 0.50
   },

   [99] = { -- box末尾
      chars = {'boxbdd', 'parbdd'},
   },

}