The plot goes like this:
some dude reach other world (I think), and has the ability to make potions. then some old woman at the alchemist guild helps him, and tells him to sell the potions at the adventurers guild, but there, the potions get broken by some adventurers, and the old lady gets mad, because that's an insult to the alchemist guild, and says she's not gonna give them potions anymore, so there's this (probably noble) adventurer girl who says she'll sell herself as a slave to pay compensation.

pic unrelated