This is a world that elves live with us humans ,after the elf paradise collupsed they have lost their immortal power and get a Side Effect like a curse make their genitals bigger and must keep fucking themself to stay alive and keep their normal elf form. But some of them failed and their body transformed into something like sexual monster that make the genitals much bigger and very very sensitive .The way to turn back is to fuck and fuck untill the genitals absorb enough human sperm. Hope you guys like it!