How NOT to Summon a Demon Lord Manga Volume 12

How NOT to Summon a Demon Lord manga volume 12 features story by Yukiya Murasaki and art by Naoto Fukuda.

In order to cure the Marked Death Disease, Diablo must raid his own dungeon to retrieve a healing talisman from his treasure trove. But when lowly adventurer Horn is carried off by a raging underground river, Diablo must leap in after to save him! Meanwhile, Rem, Shera, and Lumachina continue on as planned, only to encounter a Black Dragon!