Ever since I stumbled upon 'Daughter of Smoke and Bone' by Laini Taylor, I've been fascinated by the concept of beings that bridge the celestial and mortal realms. In that series, they're called chimaera, but more broadly, the term 'nephilim' often pops up in fantasy lore. It's borrowed from biblical texts, where nephilim were the offspring of 'sons of God' and human women. Some authors put their own spin on it—like Cassandra Clare's Shadowhunters, who are part angel but still very much human in their struggles.
What I love about these hybrids is how they embody the tension between divine power and human frailty. They're usually torn between two worlds, which makes for great internal conflict. In 'Good Omens,' Aziraphale and Crowley aren't technically hybrids, but their long-term exposure to humanity gives them a similar duality. It's that push-and-pull between ethereal purpose and earthly desires that keeps me hooked on these stories.