Tegami Bachi: Letter Bee

Lag gave the name "Niche" to a girl that was a letter whose delivery slip was incomplete and couldn't be delivered, and started taking her to her destination. Lag is enchanted with her hair while he escorts her, and on his way after dropping her off, he learns from some passersby that her destination was actually a freak-show, advertising a new attraction: A child who received the blood of the legendary creature "Maka."