Tsuihou Sareta Pashiri, Kaimono Skill SSS de Soubi Musou: Katta Mono wo Chou Kyouka Shite Saikyou Party Mezashimasu

As an apprentice adventurer, Serk was nothing more than his party's errand boy. After being constantly ridiculed and called useless, he was eventually kicked to the curb by the very comrades he served. But his former party had no idea what they’d just thrown away. They had no idea that Serk's long, thankless life of running errands had caused an incredible, new talent to blossom within him. He now wields the "SSS-Rank Shopping Skill", a unique power that makes him stronger with every single purchase. By buying and massively enhancing items, Serk is ready to become an unstoppable force on his quest to become the most powerful adventurer in the world!