In episode 4 of Mushoku Tensei S2, Rudeus Greyrat and his group encounter a pack of Luster Grizzlies and a red dragon. Rudeus, also known as Quagmire, assists in fending off these threats and earns the admiration of his companions. Despite their admiration, Rudeus declines the offer to officially join their group, as he is still searching for his mother.

During a celebration at a local tavern, a woman named Elinalise Dragonroad approaches Rudeus. She reveals that she is a former party member of Rudeus' father, Paul, and a friend of Rudeus' mentor, Roxy. Elinalise informs Rudeus that his mother Zenith is in the labyrinth city of Rapa, located near the center of the Begaritt continent.

Rudeus decides to stay in the current country over the winter before setting out to search for his mother. He learns that Roxy is also searching for Zenith and feels reassured knowing she is involved. Elinalise, who is very flirtatious, attempts to seduce Rudeus, but he is unable to respond due to his erectile dysfunction, which he has been struggling with for two years.

Rudeus receives a letter from Jenius, the vice-principal of Ranoa University of Magic, inviting him to study as a special student at the university. The offer includes access to the university's libraries and research facilities, and Rudeus would neither have to pay tuition nor attend regular classes. Despite the tempting offer, Rudeus initially decides to decline the invitation, as his family is more important to him than his magical education.

However, during a dream, Rudeus is once again visited by the mysterious being known as the Human God, who advises him to accept the university invitation. The Human God suggests that Rudeus will "regain his male potency and pride" by doing so. Encouraged by this advice, Rudeus decides to enroll at the Ranoa University of Magic and sets off for the Kingdom of Ranoa, concluding the episode.