>Book of Enoch (specifically 1 Enoch), the Watchers (fallen angels) were indeed forced to witness the mutual destruction of their offspring, the Nephilim (giants).
>According to the narrative, the Watchers descended to Earth, took human wives, and fathered the Nephilim, who grew to be savage giants that devoured all of humanity's provisions and then began to turn on and consume each other and humans. As part of their punishment, before being bound in the underworld (Tartarus), God decreed that the Watchers would have to watch their beloved children be destroyed by internal conflict and the subsequent Great Flood
Nice parable for going back in time and sleeping with the "privatives"