What would you do if you had a billion XP?

On a certain day, the once-popular MMORPG, Skillbound Odyssey, was opening its servers for the final time. Okuma Sho, a NEET, has been a major player since the game's release. On this particular day, he finds himself raging at the incompetence of his teammates and throws his chair out the window while screaming profanity in the team's chat. After his tantrum, his mother bursts through the door and physically kicks him out of the house. Bewildered, Sho has no choice but to leave the house for the first time in ages. While running away from the house, he collapses onto the ground and begins plotting his revenge; however, as he does, a plane crash lands on top of him, instantly killing him.

When Sho regained consciousness, he found himself in a strange bedroom with no memories except of a meeting with a God-like entity. After a week of getting to know his new self, he learns about his family's special skill, XP Transfer, and the long tradition of repeatedly sending XP to future generations without spending a single point; however, his parents had a different idea. Suddenly a billion XP is transferred to Sho and he is given a mission. Instead of following tradition, they want Sho to use the XP to power himself up and undercover the tradition's origins.

What will Sho do with his billion XP and more importantly, what is the meaning of his family's tradition?