With the body count well past the large number, and the demon killed in the action having dropped a Demon Crystal worth thousands of monster cores, it was time to call it a day on the second level. It was clear that Kenta and his team did not need to take any more chances than they already had, so they turned around.
Having said that, when Kenta and his team returned, they were met with the large parade of underground monsters, as well as Ai's fast magic and the duo's fast attacks. Every single one of them made it to the other side and back via teleportation in under five hours, all while the sun was at its highest point in the sky and was scorching the entire planet with its wrath.