Tegami Bachi Vol. 6 (manga)

The Lighthouse in the Wasteland

Lag finds his long-lost hero Gauche Suede! But Gauche's heart is so depleted that he has no memory of his former self, and now goes by Noir the Marauder. Lag's only hope to recover the real Gauche is a special letter bullet that will convey Lag's heart to his friend. Lag's not sure how to go about writing the perfect letter, but his Letter Bee duties offer some good lessons in connecting hearts.