"Heart failure due to a buildup of scar tissue. His heart had become weak because he was practically starving himself in Munich because inflation there at the time was ridiculous--as in several million would get you an egg--so that his then-boyfriend, Alfons Heiderich, could get the medicines he needed. Then when he got here to the Nexus, he was attacked by a version of Sloth and got electrocuted. They didn't realize what had happened until he collapsed while working on the second building several years later."