"Done!" Elena said in a cheerful voice as she stood up and showed her notepad to Das.
"Why did you stand up?"
"Because I solved the problem."
"I bet it will be wrong."
Elena puffed her cheeks and said, "What will you do if it's right?"
"I will be your slave."
Das was sure her solution would be wrong, so he said something he shouldn't have.
Das grabbed Elena's notepad and started checking the solution.
When he was halfway through her solution, he started sweating.
'What the hell?!'
He once again checked from the beginning and stopped half way.
'What the fuck?! It's correct.'
He gulped down and checked two more steps.
'They are correct too.'
Das slowly placed the notepad down and looked at Elena.
"Answer me honestly, Elena."
"What?"
"How did you cheat?" Das asked with a straight face as if he was sure Elena cheated.
Elena's face twitched as she swung her hand to slap Das.