The Unwanted Undead Adventurer: 1x7

Magic Contract

The boss turns out to be a Grand Slime. Rentt opts not to fight so Rize and Laura can gain combat experience, and they eventually destroy the slime. As the first party to arrive, they are promoted to bronze and also receive potions and a carrying case. On the way back, Rentt shows them how challenging labyrinths can be, as one floor is a giant forest whose geography changes constantly. Rize and Laura depart but hope to see Rentt again.