My Isekai Life: I Gained a Second Character Class and Became the Strongest Sage in the World! manga volume 17 features story by Shinkoshoto with art by Huuka Kazabana and Ponjea.

While on a quest to clear out an infestation of wraiths haunting a nearby forest, Yuji stumbles on a mysterious laboratory hidden among the trees. With the help of his trusty Slimes, he infiltrates the facility, stumbling on the existence of a shady and incredibly dangerous organization. To make matters worse, they somehow know all about the infamous Monster Tamer, Yuji…