Before reading this story, be aware that the passive skill system has no rules! No upgraded skill except for Gluttony Lv2 that he mentions a zillion time when everything else stays at Lv1 forever. Ultimately, the author stops giving levels and rarity to skill (white:common, green:uncommon, ...) wihout bothering to fix the previous chapters. In the end, the author doesn't edit anything related to the functions of the system throughout the entire because he's obviously too lazy to do it. He should have just said that the main character get passive skill at random.

See this! I just gifted the story: Balloon

See this! I just gifted the story: Balloon

lol