Schuld 
Min-Maxing My TRPG Build in Another World: Volume 3 [EPUB ebook] 

Putting the fey tragedy behind him, Erich arrives at the Rhinian capital and begins his term of service under Lady Agrippina at the Imperial College of Magic. There, he draws the attention of a troubling wardrobe connoisseur but has no choice but to press on and earn his sister’s tuition.
After befriending a student at the College, the two set off on one of Agrippina’s simple errands—until the Goddess of Dice turns their quick chore into a full-blown dungeon crawl! How many lovely pips will those dice show in the third session of Erich’s campaign?!