most of suguru's organs are, as he mentions, artificial, so he probably wouldn't die
Mahoro's memories somehow became a "piece" of Matthew, so before Saint departed Earth/wherever once more, she "dumped" the pieces of mahoro into one being and gave her as a gift to Suguru (i'm pretty sure she (Matthew/green haired Saint girl who's naked a lot) and Suguru are related...i think she's his grandmother or something)
