This is apparently from the episode "A duel with Dartz, part 3" (episode 179, aired in 2003):
Kaiba: So you got a dweeb army. Is that supposed to make me afraid to attack?
Dartz: No, not unless destroying an innocent soul concerns you
Kaiba: As a president of a major corporation, I have to do that everyday.
Season 4, episode 14b, "Who's Johnny?" sounds like a match.
Summary from Wikia:
When Sissy considers Johnny too gross to help her with their social studies project, he begs Susan and Mary to change his personality, as part of their grade depends on cooperation and their ability to work together.
The episode is below (second part of the video, start ...