Hybrids

"Why would they do something like that?" While Uriel was well versed in archaeology and mythology, the actual expert on cryptids of his party was Luna.

"It's simple, really. This creatures are hybrids, they can't reproduce by themselves and rely on humans to keep their population up, now that the soldiers already served their purpose they'll simply let them go. Though it seems it's been a while since any humans entered this place because they were desperate, it's been days and they're still mating."

"That certainly explains why the soldiers were so busy, but does that not apply to their male?" Uriel asked Luna.

"No. It seems only the female can procreate. The male of their species are tasked with protecting the female." Luna explained.

"Protecting them from what?" Nika asked worried. So far, this 'world' seemed completely harmless.