Normally, when a light magician didn't have enough mana to teleport to their destination point, the spell would not activate at all. That alone was why light magic was one of the safest ones to use – as long as the user themselves wanted to get hurt, the light attribute mana itself would stop its flow to prevent any harm to its user.
Still, what Zoemi used wasn't a pure copy of the teleportation from the light attribute's array of spells but a copy modified with some of the unstable properties of the shadow jump from the darkness attribute.
Hence, the spell did activate, but the moment that the boy's mana ran out, he was spat out immediately, landing in bushes by the crystal lake.
Unfortunately, the black-haired boy ended up unconscious, but on the other hand there, fortunately, wasn't anyone around who could take advantage of that vulnerable state of his.
