--So, I promised to pay my own tuition and living expenses. --Hotpot. Also, I'm Tohru.

When you're boiling something, you roughly cut them diagonally into random shapes.

Not even my father's lame jokes or the overly-sweet taste of my mother's boiled vegetables.

If you'd so kindly let me give away the answer, it's because even if you're cheating on someone or you're being cheated on, everyone laughs at bad jokes and eats over-sweet boiled vegetables.