Saitama stepped into his apartment, located within the Hero Headquarters in City-A, and heard the sound of the kitchen sink running and dishes clinking together. He peeled off his gloves and, as he tossed them into the sink, greeted Genos, who was drying the wet dishes using one of his hand cannons.

"Oh, Genos, you're back from your mission?"

"Indeed, Master," Genos responded as he began washing the gloves. "The enemy was weaker than anticipated, so I sustained no major damage, and was able to return immediately after the threat was neutralized. When I arrived back at the apartment, you were absent, so I completed some housework. Were you out defeating a monster as well?"

As they talked, Saitama changed out of his hero outfit and into some more comfortable clothes.

"Kinda."

"What do you mean, Master?"

"Well, I took care of a monster, but do you remember that short hero, Tatsumaki?

"Class-S, rank two, The Tornado of Terror; yes, I remember her well, Master. I hold mixed feelings toward her; she is the one who propelled me into a stone wall after our fight against the alien invaders, but she also assisted me in defeating Psykos, as I have told you."

The sour memory of Genos being slammed into the stone wall struck Saitama as the cyborg reminded him; he didn't really hold it against Tatsumaki, as Genos was pretty much fine after the blow, and she likely knew that he would be, but throwing his friends into walls wasn't a precedent the bald hero wanted to set.

He let the memory fade and continued, "Yeah, well, apparently she was there to take care of the monster too, and she wasn't all too happy when I stole her kill."

Genos set the now clean gloves on the drying rack and made his way over to the common area, taking a seat across from Saitama and laying his hands in his lap while giving the man his full attention.

"Master, there is no such thing as "stealing a kill". The Hero Organization does not have any kind of system allowing heroes to call kills, I am sure of it."

"That's what I told her, but she insisted anyway."

Genos paused, seeming to come to some conclusion in his mind as he eyed his master suspiciously. Saitama met the cyborg's intense stare with one of confusion; Genos was often hard to read, often due to his serious and confrontational nature, so Saitama couldn't determine what may have been on his mind.

"Uhh, Genos? You good?" Saitama asked, not knowing whether or not he should be concerned.

"Master, I mean no offense," Genos responded, "but did you engage in another battle with Miss Tatsumaki over something so trivial?"

Relieved, Saitama relaxed his shoulders as he answered his disciple, "Oh, no, nothing like that, but she did press me into paying her back, so I just decided to let her come to lunch with me."

Genos cocked his head slightly. "Is it wise to encourage Miss Tatsumaki's bratty behavior by agreeing to her demands for unearned reparations?"

Saitama pondered the question for a moment. "Well, you bring up a good point, and I guess the answer is no, but if giving in a little bit stops her from complaining, then I think it's worth it."

"I see," Genos said as he retrieved his notebook and pencil from a pocket, scribbling down notes as he continued, "By capitulating to Miss Tatsumaki's demands, you pacified her, preventing further insolence and disruption. This strategy is detrimental in the short-term, but yields greater benefits in the long-term; very wise, Master."

Saitama sighed internally at Genos, whose ability to turn a simple explanation or recounting of events into a life-lesson never ceased to surprise and irk him. Saitama, like usual, chose to ignore his disciple's note-taking and added, "But really, the main reason I invited her to lunch was because I wanted to check on her."

Genos paused his note-taking and looked up at Saitama. "What do you mean, Master?"

"Well, after she and I had our little battle a couple weeks ago, I told her that she should stop destroying other people's stuff. I've been keeping an eye on the news to see how her battles have been going, and she seems to be doing better. When I talked to her, her attitude seemed to have changed a bit too. She was plenty snarky, but less…mean, I guess? I don't really know, it was just good to check in on her."

Saitama didn't want to list the last reason he had decided to invite her to lunch with him, being that he had been desiring some sort of company that was a bit more lighthearted than Genos. He felt a little bad, like he was lying to him in a way, but he really didn't want to offend Genos, or worse: make him think he needed to change. Saitama often enjoyed Genos' directness; he had been mostly following Saitama's twenty-words-or-less rule and kept conversations focused on the interesting or important parts. Of course, Genos was also very helpful, what with all the reminders he gave, suggestions he made, and general housekeeping chores he took care of. Really, though, Genos was his friend, and as much as the cyborg got on his nerves at times, he didn't ever want to lose what made Genos, Genos.

"But," Saitama continued, pushing the thoughts out of his mind, "I actually had a pretty good time." Genos was surprised at this, as Saitama had only ever spoken annoyedly about Tatsumaki, and was seldom keen on involving others in activities outside of hero duties. "When she's not all angry or defensive, she can actually be kinda funny and sarcastic."

"Master Saitama, if Miss Tatsumaki has disrespected you, I will personally seek her out and scold her for doing so," Genos threatened, going from surprised to angry in a second as he raised a clenched fist, intent on ensuring his master received the respect he deserved.

"No, no, Genos, it's okay. I meant sarcastic in a good, joking kind of way."

Genos lowered his fist, once again confused by his master's reaction, and to the situation as a whole. "Master, if I may make an observation, you seem unusually unperturbed by this whole series of events."

"Unper- what?"

"You have never shown an interest in spending time with Miss Tatsumaki or engaging in activities with others outside of hero duties and video games, yet having indulged in both, you seem satisfied, even happy, immediately after the fact. You are usually eager to avoid such situations and typically voice your irritation before and after the event. Is there something I am not understanding about this situation?"

"I mean, I guess you're right, that is how I usually feel, but like I said, she was actually kinda fun to have lunch with. That's really all there is to it," Saitama answered as he picked up one of his mangas, laid back, and began reading.

Genos furrowed his brow. Something was going on with his master; not anything bad, necessarily, but something. Saitama enjoying Tatsumaki's company was strange, but he had offered a reasonable explanation for that; the thing that was really odd, and what piqued Genos' interest in the matter, was that Saitama had actually enjoyed an activity that wasn't related to heroing. After spending the better of the past three months with the man, Genos had come to realize that Saitama was suffering from what he believed to be depression. Everything he enjoyed and all the passion he described himself having had was now gone. The only thing his master ever seemed to find enjoyment in was video games with King, and even that seemed like more of a stressful endeavor than an enjoyable one.

Genos couldn't remember the last time he had heard Saitama say that he had fun or that he had enjoyed something; in fact, he wasn't sure he had ever heard it at all. That's why Genos was interested; Saitama had enjoyed himself, potentially for the first time since they had known each other, and the only new variable…was Tatsumaki.

That begged the question: What had she done to bring Saitama out from his shell of apathy?

There were a variety of possibilities, but if he wanted to find the reason, Genos would have to get creative…

*3 days later*

"Master?" Genos asked Saitama, who was sitting on the ground, reading one of his mangas.

"Yeah?"

"Would you be open to hosting another hot-pot for our friends and associates?"

Saitama looked up from his reading with a confused expression. "Ehh, not really. What makes you want to do another hot-pot?"

"Now that we live in the Hero Headquarters, I feel it may be beneficial to socialize and interact with the other heroes, especially given that you have reached the A-Class. It helps to show that you are active within the association and may encourage its members to send you out on more missions."

While that was part of Genos' reasoning for suggesting another hot-pot, it certainly wasn't the only one, nor the most important. Over the last several days, Genos had been deciding on how best to approach the situation, to determine how Tatsumaki got Saitama out of his shell. After much thought, consideration, and a wide variety of scrapped plans, Genos finally decided that simply observing their interaction would yield the best results. Of course, this strategy had only proven partially successful in his quest to become strong like his master. Documenting Saitama's habits and words of wisdom had yielded less results than anticipated, but the strategy had provided at least some results, and would hopefully do the same in this scenario.

Additionally, this plan had a built-in backup; even if he was unable to observe the pair, or if the information was unserviceable, then he would likely be able to get at least some information from Fubuki, whom he planned on inviting. Fubuki was like Genos, in that she examined people and situations closely; she may have noticed the change in her sister that Saitama had, which may help explain his behavior. Including her in the investigation was of little risk, but offered the chance at some valuable information and an additional set of eyes, which in and of itself was of incredible value. Of course, this would mean that he would be getting more involved with Fubuki, much to his distaste, as she would certainly be interested in the on-goings of Tatsumaki and Master Saitama.

"I don't know, that sounds boring," Saitama responded nonchalantly, "Plus, this apartment is cramped enough as it is; I'm not sure how many people we could comfortably fit in here,"

"I have researched a new spicy lamb hot-pot recipe that has been rated five out of five stars," Genos countered, knowing that the meal itself would likely be enough to entice the man.

Saitama shot Genos an inquisitive stare and asked, "How many total reviews does it have…you remember what I told you about trusting dishes with low review counts…"

"Of course, master. "If it has less than one thousand reviews, it's not to be trusted," he quoted before reassuring his master, "The spicy lamb hot-pot has over two thousand reviews, only four of which have rated the dish at one star."

"Whoa, really, it's that good?!" Saitama exclaimed, his eyes wide and taste buds tingling at the mere thought of the dish. "So, when were you thinking about doing it? Saturday?"

"Indeed, I believe Saturday evening would be a good time."

"Cool. We'll head out to the market tomorrow to buy fresh ingredients. And Genos, let's not invite too many people, okay? Like I said, this apartment's really not meant to fit a bunch of people."

"Yes, master. Does this mean I have your permission to invite someone of my choosing?"

"Uhh, yeah, of course, invite whoever you want…again, not too many people."

"Yes, master. Thank you."

Saitama had no reason to worry about overcrowding; Fubuki was the only one Genos would be inviting, and she was already biting at the bit to be around the two heroes, always trying to convince them to join the Blizzard Bunch.

The last thing Genos had to do was get Saitama to invite Tatsumaki. He would do it himself, but that would likely make it obvious he was up to something. Plus, Saitama inviting her over himself would actually support his theory.

"Master, if you are on good terms with Miss Tatsumaki, perhaps inviting her would be a good idea. She has significant sway amongst the higher ups in the Hero Association and it would allow you to check in on her again."

Waiting in anticipation for an answer, Genos noticed Saitama light up at the mention of Tatsumaki; the change in his facial features was subtle, but definitely there. However, the glow quickly faded as he responded, "Nah, she probably wouldn't care for that sort of thing." And with that, the bald man went back to flipping through the manga, looking slightly disheartened

Disappointed, Genos nodded at his master's response. The opportunity cost was great, but he figured that he should be able to gain at least something from Fubuki. With the prep-work complete, all that was left to do was to send out the invites and go shopping.

"The process may be slow," Genos thought as he went to continue cleaning, "but I will find out what happened between Miss Tatsumaki and Master Saitama."