...Until a disaster wipes out the little bit of universe he's been sustaining, leaving him in The Nothing After Death, forever.
The eventual boredom still applies.
Played For Laughs: Steven becomes immortal, and goes through a series of over-the top, amusinglypainful events, mourning his condition all the way.
Played For Drama: Steven eventually becomes cold, bitter and disassociated from humanity as everyone he knows dies, everything he knows changes around him. He begins to view himself as not human and those around him as objects for his amusement.