Marcel was torn between revealing the truth and keeping quiet. As he was determined to get Aria for himself and separate her from Ace, he started to speak, saying "It Ac-", but immediately thought better of it. He realized that speaking up would damage both Aria's and his own reputation.
"God, thank you," Marcel thought. "Now, if I dare say something to them, it will be a mess. Aria's image, not just hers but mine, will be ruined. It will be revealed that I love her and even kissed her forcefully. No, no, no, I should zip my lips."
The principal, noticing Marcel's hesitation, asked, "What did you say, my son? We're waiting." Marcel stuttered, "N-nothing." His father, Mr. Remy, asked, "What did you mean by nothing?" Marcel replied innocently, "Father, I don't know who did this to me."