 Why is Thig's return to Earth bittersweet?
His task now was to bring a native, intact if possible, back to the carefully buried space cruiser where his two fellows and himself would drain the creature's mentality of all its knowledge. Feebly he had punched a key two days ago and a $ sign had appeared. An hour later, his scars and altered cartilage already healed and painless, Thig again scraped sand over the entrance to the space ship and set out along the moonlit beach toward the nearest path running inland to his home. Men had no mates on Ortha, sex had been overthrown with all the other primitive impulses of barbarism; so he was incapable of understanding the emotions that swept through his acquired memory.
 Though he wants it, he'll never truly belong. He'll always be an otherworlder.
 His Orthan background will always be at odds with his new life.  It's grueling to remember what he did to Terry, and to always have to be him now.  Though he wants it, he'll never truly belong. He'll always be an otherworlder.  He misses his life as an Orthan, even though he's come to enjoy Earth.