Apollo held up his hands to profess his innocence - he wasn't interfering with Clio's new beau! At all! Here everyone was thinking the worst of him. Clio was happy and that was all he wanted.
As for Melpomene, well - he dropped his hand to pick up his wine again. "She won't die," he said, with certainty. "If Artemis is still playing with her Sheriff, I'll be there. Even if Artemis is back, I'll be there. She will not die. No fucking way Ares' kid is taking her."