A/N: (Minor Fix November 15, 2015) This is my first story and to be honest I'm bad at writing stories, but this won't just get out of my head. So, I write this. Just imagine the first fight with Berserker, with Saitama replace Heracles.
Disclaimer: One Punch Man belongs to ONE and Yusuke Murata, Fate/Stay Night belongs to Type Moon.
"Kill them, Berserker!" Said the little girl.
The man behind her roars and then dash toward the other group of two teenagers and someone with yellow raincoat. Then the yellow raincoated man take off the coat and turns out to be a woman dressed like a knight in blue. She swings her hand as if she holds a sword and repel Berserker's punch.
"WEEKEND SALES!" Berserker roars which makes everyone except the little girl shocked.
Berserker hit the knight in the guts and she tried to block it with her invisible sword. The Knight believed that at worst she will be pushed so far from the two teenagers. What happened next shocked her. He broke her sword, punched her in the guts cleanly and a big hole replaced it. The knight in blue fall to her knees and disappeared.
"SABER!"The boy teenager run to the place where the knight was.
"We're fucked..." Said the teenager girl in who fall in her knees in despair.
"Good bye, Onii-chan." The little girl commands Berserker to kill both of them.