肝 (gān): Liver. In Chinese culture and medicine, the liver is associated with planning and emotional balance.
胆 (dǎn): Gallbladder. The gallbladder is strongly linked to courage and decisiveness. For example, `胆量 (dǎnliàng)` means “courage.”
相 (xiāng): Mutually, each other. This character emphasizes that the action is reciprocal.
照 (zhào): To shine upon, to illuminate, to reflect.
The characters combine to create a powerful image: the liver and gallbladder, two vital and interconnected organs, are shining light upon one another. This illustrates a relationship where there are no dark corners or hidden secrets. Everything is out in the open, based on mutual respect, loyalty, and complete sincerity.