Whatever it's precise meaning...this is a very powerful dream... and although it was frightening and violent...it may actually be quite positive. Blood is the life force...energy...strength. In Chinese and Christian symbolism, blood and water (clear fluid) are complementary...the yang (masculine) and yin (feminine) principles, and the life of the body and life of the spirit. Glass has a similar meaning to crystals...purity, spiritual perfection, knowledge, the pure mind....transformation from one plane to another. And death is always an indication of transformation...preceeds rebirth and reunites body and spirit. You encountered this man when you went to a toilet...place of letting go of what is no longer needed. Are you going through a major transformation at this point in your life?...connecting with your spiritual aspect?...turning more to your intuition as opposed to your intellect?...releasing painful emotions?...inner battles? Destruction is always accompanied by creation. Has something new recently appeared in your life or are you embarking on a major change? It seems like you are prepared for the challenge...even if it is scaring you.