Work as a Postman in Another World and Then Pick up a Vampire

A certain college student who just passed the final week unfortunately traveled to a different world and found that he was the weakest human being with little magical power and the lowest physical strength. Just when he thought his life was over, he awakened his only talent - the inventory. Time stands still, absolutely safe, regardless of distance, access as you wish. Okay, let the geniuses get involved in fighting and saving the world. I, Cole, the number one postman in another world, officially take up my post! "You have a new order: to deliver snow-capped ice cream that will last for thousands of years to the Elf Queen." "Urgent: Escort the dwarf master's hammer through the orc battlefield!" "Special commission: Bring a message from the deceased back to the Dragonborn Ancient Tomb..." The vampire girl Letitia did not expect that she would be saved by such an ordinary human being—— I never thought that I would stay by his side, helping him count his money during the day, and... Secretly counting his heartbeats at night. "Hey, human, when are you going to sign for my 'package'?" She licked her fangs, her red eyes flashing. Cole looked at the extra "White-haired and Red-Eyed Vampire (temporarily stored)" in the inventory and felt a headache on his forehead: "Sir, living creatures... Are not within the scope of business——"