Spoiler Summary [Click to show or hide]:
After the intense battle from the previous chapter, OPM Manga Chapter 29 gets a mild mood as everything…
…seems back to normal and Saitama receives his promotion.
In this chapter, a jet fighter drops a package with a parachute containing mail from fans. Saitama and Genos encounter the package and take the letters addressed to them.
As they open and read the letters, some criticize and insult Saitama, while one express gratitude. Among the letters is an official Certificate of Promotion from the Hero Association, elevating Saitama to Class C Rank 1.
Saitama reports to the Hero Association Headquarters in City Z, where executives congratulate him on his rank advancement.
They propose further promotion to Class B, but during a psychological exam, some executives question the legitimacy of Saitama’s entrance exam results. The executives consult Amai Mask, who approves the promotion.
With the official approval, Saitama receives his new certificate and becomes Class B Rank 101. Later, at a ramen shop, he encounters Mumen Rider, an injured hero who had sent the thank-you letter that morning.