What if Saitama has a biological sister?

Other Class S

After the incident about the deep sea king, Saitama become Class-B, Nancy was very happy of that news.

But one day, they were invited to Bang's Dojo.

His top disciple Charanko was blushing at the sight of Nancy who was acting bold and boyish.

*Bang's Dojo*

Genos: "So old man, what do you want from us?"

Bang: *brushes his mustache* "well you might be interested in my martial arts?"

Saitama: "I don't need like that to be honest"

Charanko: "hey stop being disrespectful to Bang Sensei, he is the most respectful and feared martial artist!"

Bang: "enough Charanko! Those people are stronger than me!"

Charanko: "b-but..."

Nancy: "yeah, listen to your master"

Charanko: "don't talk to me!" *Looks away while blushes*

Saitama: "hey your face is overheating, what's up? The weather was fine"

Charanko: "n-nothing! That's none of your business baldy!"

Genos: "is this your best disciple?"

Bang: "yeah, he is....my other disciples are leaving me behind.."

Genos: "but why?"

Nancy: *listens and curious*

Bang: "I have a top disciple before who went rampage in my dojo, I kicked him out after that, in result all of my disciples start to leave after getting beaten up by him"

Nancy: "hoh? Is he strong?"

Bang: "well, he is..."

Saitama: "if you are only inviting us for being one of your disciple, well we might just leave for now--"

Someone just barges, a guy in suit who is part of hero association headquarters, gasping air from walking up in the hill since Bang's Dojo is in the top of the hill.

HA Assistant: "M-Mister bang! Emergency meeting! All Class S are called for the meeting--"

Genos and Nancy: "???"

HA Assistant: "oh, I'm glad 2 more class S is with you, it saves my time.."

Genos: "Sensei, since we are called, do you want to come with us?"

Nancy: "yeah he is right, if anyone disrespect you there, I'll beat them" *smiles boldly"

Saitama: "stop that little sis, and I'll come since my sister and Genos is also coming"

*Inside the Hero Association HQ halllway*

A samurai guy greet Bang and others.

???: "Oh mister Bang" *grins with a toothpick in his teeth*

Bang: "mister Atomic Samurai! Nice to meet you"