Urban Dictionary: evil
Girls are evil
理系ジョーク
First we state that girls require time and money
Girls = Time * Money
And we all know that "time is money"
Time = Money
Therefore
Girls = Money * Money = Money squared
And because "money is the root of all evil"
Money = square root of Evil
Therefore
Girls = (square root of Evil) squared
And we are forced to conclude that
Girls = Evil
QED.