Warning: This article contains spoilers for One-Punch Man Chapter 155, "Results," One, Yusuke Murata, John Werry, and James Gaubatz, available in English at Viz Media and Manga Plus.
One-Punch Man's "Monster Association" Arc featured the biggest war in the series yet. The Hero Association and Monster Association have both brought out every character at their disposal to finally rid themselves of the other's existence. As an S-Rank Hero, the fan-favorite Demon Cyborg responded to the call of duty. Meanwhile, his master was also keeping himself busy. The peculiar pair finally met up again in Chapter 155.
The chapter started with Saitama, Flashy Flash, and Oculette finally returning to the surface after their little adventure. King spared no second and ran towards Saitama in glee and great fervor. Saitama, however, went to his subordinate after noticing his condition, ignoring whatever other threats remained. The first thing he asked Genos was whether or not he was alright, then followed it up with an inquiry of who did that to him.
That exchange was just the start of their meeting, literally. Genos gave Saitama a brief overview of what happened, especially how King obliterated the other high-tier monsters. As if on cue, King also arrived and told the Bald Cape of his student's contributions, especially how he defended Terrible Tornado. Saitama praised Genos for his efforts, but the Demon Cyborg cast his doubts about getting stronger to Saitama given that he failed in his attempt at self-destruction. Like a prim and proper master, Saitama touched Genos' core and said, "Doesn't that mean you got stronger in here?"
The last time Saitama and Genos were together was when the whole gang had a hotpot in Saitama's place, which was literally years ago. Since then, Genos joined the fight against the top brass of the Monster Association. He helped and saved numerous heroes on various occasions and also joined hands with the other S-Class heroes to take down Psychos. Saitama, on the other hand, infiltrated the monsters' lair after hearing constant rumbling underground. He went further and further down and met Flashy Flash and Oculette along the way. It's not until Bang found them that they manage to get transported back to the surface.
Fans may have not noticed how long it's been since the two main characters were together since the two still had frequent appearances. Garo's consecutive level-ups also largely contribute to this. However, Murata is clearly well aware of this fact. The master-disciple reunion was commemorated via a glorious full-colored double spread, accentuated by a colorful constellation from the three-way fight between Flashy Flash, Garo, and Platinum Spermatozoon.
Saitama isn't necessarily famed for being an intimate character. He only accepted Genos and allowed him to live with him after the latter proposed paying a good chunk of his rent. However, this recent interaction between the two served as proof that Saitama has slowly warmed up to his student. Even though Saitama telling Genos that a certain part (his core) got stronger was done matter-of-factly, it is undeniable that he rushed to his student after seeing his condition. He even ensured Genos' condition and was ready to repay whoever did that to him.
Saitama and Genos' relationship is bound by mutualism, initially at least. The long-overdue reunion -- portrayed in glorious two full-colored pages -- proves that their dynamic has changed. Saitama has warmed up to Genos and now puts his student in high regard.
