My Bible is an 'Otherworld Summoning Story'

Ernesto is the third son of the Violetti Count family. As he cannot inherit the family estate, he chooses the path of an adventurer to make a living. His only reliable assets are his barely usable unique skill, 'Magic Bullet', and the knowledge from the family's treasured book, 'Otherworld Summoning Story'. Despite being viewed with prejudice because of his 'disaster-level' siblings, he diligently attends the guild every day. This is the story of his modest efforts to rise as an adventurer, using his beloved bible, the family's treasured book 'Otherworld Summoning Story', while being second-rate in both swordsmanship and magic. The main story is complete for now.